Exercise Tool Kit

Text Size:+-
412.892.5650
5241 Brownsville Rd Pittsburgh, PA 15236
  • Home
  • Client Education
  • Kinesis Physical Therapy
  • Contact Us

Heritability & Physical Performance

Posted on 03.8.15

_______

The form and function of the human body is determined by numerous environmental and genetic factors. Characteristics associated with physical performance are ultimately an expression of our genetic blueprint under particular environmental conditions.

If a sportsman has an “ideal” genetic profile and the environment is optimal then we would expect performance to be of a high level. If the environment is less than favorable we can predict that performance would suffer. The following is meant as an introduction to the influence of human gene variation on physical performance.

Heritability DNA_methylation

Heritability is the proportion of observed variation in a particular trait that can be attributed to inherited genetic factors in contrast to environmental.1 

Scientists calculate heritability as a value between 0.0 (no contribution of genes to the variation of a trait) to 1.0 (genes are the only reason for the variation in a trait).

As an example, the heritability of height is estimated to be 0.8 or 80%.2 The other 20% would be attributed to variation in environmental factors such as the availability of adequate nutrition.

Inheritance and Endurance

Maximum aerobic capacity is a measure of aerobic fitness and is associated with success in endurance sports.1

Heritability of maximum aerobic capacity has been estimated to be between 4o and 71% percent.4,5 This demonstrates that our genes have a significant effect on our aerobic capacity and in turn potential success in endurance sports.

Inheritance and Muscular Strength 

Maximum strength is the maximum amount of force that can be generated during a voluntary muscular contraction. This is an important fitness quality because we know maximum strength is associated with markers of sport performance such as sprint speed.6

Heritability of maximum strength is estimated to be between 29-82%.7,8 This indicates that our genes have a significant effect on the expression of physical strength and in turn potential success in strength sports.

As a side note, the eccentric component involved in maximum strength may be more heritable than the concentric element. This has potential implications for the relation between genetics and eccentric activities such as those involved in downhill skiing.

The list goes on…

Contributions from our genes are numerable and associated with all fitness qualities including susceptibility to injury and response to training. The overall effect of our genes is thought to be responsible for 66% of the difference in athletic status while the remaining 44% is thought to be environmental.11

In addition to the form and function of our bodies genes are also significantly associated with psychological determinants of physical performance such as the motivation to train.8

Bottom Line (TL;DR)

Variation in human performance is greatly influenced by our genes.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1.http://www.merriam-webster.com/dictionary/heritability
2. Golan, David, and Saharon Rosset. “Accurate estimation of heritability in genome wide studies using random effects models.” Bioinformatics 27.13 (2011): i317-i323.
3. MIDGLEY, ADRIAN W., LARS R. MCNAUGHTON, AND ANDREW M. JONES. “TRAINING TO ENHANCE THE PHYSIOLOGICAL DETERMINANTS OF LONG-DISTANCE RUNNING PERFORMANCE.”SPORTS MEDICINE 37.10 (2007): 857-880.
4.Bouchard, C. L. A. U. D. E., et al. “Aerobic performance in brothers, dizygotic and monozygotic twins.” Medicine and science in sports and exercise 18.6 (1986): 639-646.
5. Mustelin, Linda, et al. “Associations between sports participation, cardiorespiratory fitness, and adiposity in young adult twins.” Journal of Applied Physiology 110.3 (2011): 681-686.
6.CRONIN, JOHN, ET AL. “DOES INCREASING MAXIMAL STRENGTH IMPROVE SPRINT RUNNING PERFORMANCE?.” STRENGTH & CONDITIONING JOURNAL 29.3 (2007): 86-95.-95.
7. Thomis, M. A. I., et al. “Inheritance of static and dynamic arm strength and some of its determinants.” Acta Physiologica Scandinavica 163.1 (1998): 59-71.
8.Costa, Aldo M., et al. “Genetic inheritance effects on endurance and muscle strength.” Sports medicine 42.6 (2012): 449-458.
9.Bouchard, Claude, et al. “Familial aggregation ofV˙ o 2 max response to exercise training: results from the HERITAGE Family Study.” Journal of Applied Physiology 87.3 (1999): 1003-1008.
10.Sports genomics: Current state of knowledge and future directions

Heritability & Physical Performance

Posted on 03.8.15

_______

The form and function of the human body is determined by numerous environmental and genetic factors. Characteristics associated with physical performance are ultimately an expression of our genetic blueprint under particular environmental conditions.

If a sportsman has an “ideal” genetic profile and the environment is optimal then we would expect performance to be of a high level. If the environment is less than favorable we can predict that performance would suffer. The following is meant as an introduction to the influence of human gene variation on physical performance.

Heritability DNA_methylation

Heritability is the proportion of observed variation in a particular trait that can be attributed to inherited genetic factors in contrast to environmental.1 

Scientists calculate heritability as a value between 0.0 (no contribution of genes to the variation of a trait) to 1.0 (genes are the only reason for the variation in a trait).

As an example, the heritability of height is estimated to be 0.8 or 80%.2 The other 20% would be attributed to variation in environmental factors such as the availability of adequate nutrition.

Inheritance and Endurance

Maximum aerobic capacity is a measure of aerobic fitness and is associated with success in endurance sports.1

Heritability of maximum aerobic capacity has been estimated to be between 4o and 71% percent.4,5 This demonstrates that our genes have a significant effect on our aerobic capacity and in turn potential success in endurance sports.

Inheritance and Muscular Strength 

Maximum strength is the maximum amount of force that can be generated during a voluntary muscular contraction. This is an important fitness quality because we know maximum strength is associated with markers of sport performance such as sprint speed.6

Heritability of maximum strength is estimated to be between 29-82%.7,8 This indicates that our genes have a significant effect on the expression of physical strength and in turn potential success in strength sports.

As a side note, the eccentric component involved in maximum strength may be more heritable than the concentric element. This has potential implications for the relation between genetics and eccentric activities such as those involved in downhill skiing.

The list goes on…

Contributions from our genes are numerable and associated with all fitness qualities including susceptibility to injury and response to training. The overall effect of our genes is thought to be responsible for 66% of the difference in athletic status while the remaining 44% is thought to be environmental.11

In addition to the form and function of our bodies genes are also significantly associated with psychological determinants of physical performance such as the motivation to train.8

Bottom Line (TL;DR)

Variation in human performance is greatly influenced by our genes.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1.http://www.merriam-webster.com/dictionary/heritability
2. Golan, David, and Saharon Rosset. “Accurate estimation of heritability in genome wide studies using random effects models.” Bioinformatics 27.13 (2011): i317-i323.
3. MIDGLEY, ADRIAN W., LARS R. MCNAUGHTON, AND ANDREW M. JONES. “TRAINING TO ENHANCE THE PHYSIOLOGICAL DETERMINANTS OF LONG-DISTANCE RUNNING PERFORMANCE.”SPORTS MEDICINE 37.10 (2007): 857-880.
4.Bouchard, C. L. A. U. D. E., et al. “Aerobic performance in brothers, dizygotic and monozygotic twins.” Medicine and science in sports and exercise 18.6 (1986): 639-646.
5. Mustelin, Linda, et al. “Associations between sports participation, cardiorespiratory fitness, and adiposity in young adult twins.” Journal of Applied Physiology 110.3 (2011): 681-686.
6.CRONIN, JOHN, ET AL. “DOES INCREASING MAXIMAL STRENGTH IMPROVE SPRINT RUNNING PERFORMANCE?.” STRENGTH & CONDITIONING JOURNAL 29.3 (2007): 86-95.-95.
7. Thomis, M. A. I., et al. “Inheritance of static and dynamic arm strength and some of its determinants.” Acta Physiologica Scandinavica 163.1 (1998): 59-71.
8.Costa, Aldo M., et al. “Genetic inheritance effects on endurance and muscle strength.” Sports medicine 42.6 (2012): 449-458.
9.Bouchard, Claude, et al. “Familial aggregation ofV˙ o 2 max response to exercise training: results from the HERITAGE Family Study.” Journal of Applied Physiology 87.3 (1999): 1003-1008.
10.Sports genomics: Current state of knowledge and future directions

Repeated Sprint Ability: An Introduction

Posted on 04.23.14

_______
Popular sporting activities such as tennis and many team sports require the athlete to repeatedly perform bouts of near-maximum to maximum efforts, interspersed with periods of recovery. These intense efforts are generally referred to as “sprints” and typically last <10 seconds. Recovery periods are usually brief, lasting <60 seconds. The ability to repeatedly sprint with little recovery is a component of fitness that requires it’s own definition, assessment procedures, and training strategy.

Sprinting Terms

  • Sprint exercise that lasts < 10 seconds with recovery periods < 60 seconds is referred to as repeated sprint exercise.1
  • The ability to perform RSE is termed repeated sprint ability (RSA) and is an important fitness quality in many team and racket sports.1,2,3,4  As the number of repeated sprints increases, the athlete will fatigue, which results in a decline in sprint speed.  A greater loss in sprint speed will result in decreased performance.  This reduction in sprint speed is common toward the end of sporting matches.1
  • Intermittent sprint exercise is different from RSE as it allows for full to near-full recovery between bouts of sprinting <10 seconds.1 Near to full recovery may take 60-300 seconds.

Relation to Other Fitness Qualities *

From a fitness perspective RSA seems to have a closer relationship with qualities of short sprinting than maximum aerobic capacity (VO₂ Max). In a population of well trained Australian Rules football players, the strongest predictor of RSA was found to be the fastest individual 30-meter sprint time.5

Maximum aerobic capacity plays a role in RSA but it does not seem to be strongly correlated.9 There seems to be a stronger relationship between other markers of aerobic fitness such as velocity at lactate threshold (vLT) and, to a lesser extent, velocity at VO₂ Max (vVO₂ Max).6 This is important to know in order to help structure training.

* For a general background on VO₂ Max and lactate threshold please click on the links. While these articles are in reference to running, much of the information can be generalized to racquet and team sports.

Testing

There are a number of ways to test RSA.  Established tests for certain sports such as soccer (e.g. the Bangsbo Soccer Sprint Test) exist, but testing can be customized as the athlete/coach sees fit.

Repeated Sprint Ability Test

photo (1)

Testing Procedure Adapted from Pyne et al.

  • Warm-up for 10 minutes performing low-intensity running dynamic and static stretches as well as 30-meter acceleration efforts. Ensure the warm-up is the same each time the athlete is tested.
  • Perform 6 x 30 m repeated sprints
  • Rest/walk for 20 seconds between sprints
  • Each sprint is to be timed

This is a sample test procedure. Factors such as distance of sprints and rest intervals can be manipulated.

Sprint Decrement Calculation

The following calculation provides the athlete with data on how sprint speed decreases over subsequent sprinting efforts. It provides the athlete with a measure of their RSA. This can be used as a test-retest tool to determine the effectiveness of training or used to compare with other athletes.

Sprint Decrement Score (%) =  {(Sprint 1 + Sprint 2 + . . . +Sprint 6) / (Best Sprint X 6) – 1}

Training

What types of training may be valuable to the athlete who wishes to improve repeat sprint ability?

Repeat Sprint Exercise- Actually performing repeat sprint exercise or interval training may help develop RSA.  An example would be:

  • 3 sets of 4-second sprints, with 20 seconds of recovery between sprints.  Recovery between sets would be 4.5 minutes.

Sprint Training- Improving single best sprint performance may help improve RSA.  This is based on the notion that faster short sprint speed performance seems to be associated with better RSA.7

Lactate Threshold Training- Training at or above the lactate threshold may be beneficial as there is a relationship between vLT and RSA.  For the athlete involved in team sports, small-sided games may help as this often requires the athlete to perform at or above the lactate threshold.

Strength Training- Strength training seems to be beneficial for improving RSA particularly when shorter rest periods are utilized (e.g. 20 seconds as opposed to 80 seconds).10

Bottom Line

Repeated sprint ability is an important component of many racquet and team sports. Although there is not abundant evidence on the best ways to train RSA, it can be assessed and improved.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1.Girard, Olivier, Alberto Mendez-Villanueva, and David Bishop. “Repeated-Sprint Ability—Part I.” Sports medicine 41.8 (2011): 673-694.
2. Wragg, C. B., N. S. Maxwell, and J. H. Doust. “Evaluation of the reliability and validity of a soccer-specific field test of repeated sprint ability.” European Journal of Applied Physiology 83.1 (2000): 77-83.
3. Dawson, BT, Fizsimons, M, and Ward, D. The relationship of  repeated sprint ability to aerobic power and performance measures  of anaerobic work capacity and power. Aust J Sci Med Sport 25:  88–92, 1993       
4.Spencer, Matt, et al. “Physiological and metabolic responses of repeated-sprint activities.” Sports Medicine 35.12 (2005): 1025-1044.     
5.  Pyne, David B., et al. “Relationships between repeated sprint testing, speed, and endurance.” The Journal of Strength & Conditioning Research 22.5 (2008): 1633-1637.
6. Glaister, Mark, et al.“The reliability and validity of fatigue measures during multiple-sprint work: an issue revisited.” The Journal of Strength & Conditioning Research 22.5 (2008): 1597-1601.
7. da Silva, Juliano F., Luiz GA Guglielmo, and David Bishop. “Relationship between different measures of aerobic fitness and repeated-sprint ability in elite soccer players.” The Journal of Strength & Conditioning Research 24.8 (2010): 2115-2121.6.
8.Hill-Haas, S., et al. “Effects of rest interval during high-repetition resistance training on strength, aerobic fitness, and repeated-sprint ability.” Journal of sports sciences 25.6 (2007): 619-628.
9.Aziz, A. R., M. Chia, and K. C. Teh. “The relationship between maximal oxygen uptake and repeated sprint performance indices in field hockey and soccer players.” The Journal of sports medicine and physical fitness 40.3 (2000): 195-200.
10.Hill-Haas, S., et al. “Effects of rest interval during high-repetition resistance training on strength, aerobic fitness, and repeated-sprint ability Journal of sports sciences 25.6 (2007):619-628.
11.Serpiello, Fabio R., et al. “Performance and physiological responses to repeated-sprint exercise: a novel multiple-set approach. “European journal of applied physiology 111.4 (2011):669-678″

 

Running: Maximum Aerobic Capacity (VO₂ Max)

Posted on 02.28.14

_______

Distance running is an activity that relies heavily on the ability of the lungs and heart to supply oxygen to skeletal muscles in order to produce energy. In theory, the more oxygen a runner is able to provide working muscles the more effectively they should be able to perform.

The maximum rate at which an individual consumes oxygen during incremental exercise is termed VO₂ Max or maximum aerobic capacity. This is a measure of aerobic fitness and is associated with success in endurance sports.1

Pheidippides

Pheidippides

What is the VO₂ Max of high level distance runners?
High VO₂ Max values are associated with elite endurance performance. Maximum aerobic capacity values of elite distance runners have been reported to be between:2

  • 60-85 mL/kg/min in men and 55-72 mL/kg/min in women

As a reference it is not unusual for untrained individuals to have values between:

  • 38-52 mL/kg/min in men and 30-46 mL/kg/min in women.

A high VO₂ Max does not always equal running success. Other physical/physiologic factors such as running economy and velocity at lactate threshold are also extremely important.

How can VO₂ Max be determined?
Incremental exercise testing in a lab setting would be the gold standard but several field tests have been proposed.  One field test which gives a good estimate of Vo2 max in athletes and would be specific to running is the 12 minute run test.3

Materials

  • Running track although a treadmill with a 1% grade may be acceptable
  • Measuring tools to help determine distance
  • Timer

Testing

  • Warm up.  Make sure the warm-up is the same each time you test to ensure you can accurately assess improvements.  A sample warm up could be to perform a 5 minute easy run, 7 minutes of light stretching and 3 minutes of a more vigorous jog.
  • Run as far as possible for 12 minutes.  It is permissible to walk if needed.
  • Record distance covered in meters. 

VO₂ Max = (meters covered in 12 minutes – 504.9)/44.73 = (___)mL/kg/min

To help set training intensity it can be useful to have an estimate of velocity at VO₂ Max (vVO₂ Max).  The vVO₂ Max is the minimum running velocity at which VO₂ Max occurs. This is a measure of distance/time (km/h) and an can be calculated as follows:4

vVO₂ Max = VO₂ Max/3.5

vVO₂ Max can typically be sustained for ~6 minutes. With this in mind another way to estimate vVO₂ Max may be to determine maximum distance covered during a 6 minute time trial and convert to km/h.

Improving VO₂ Max 
Once the runner has an idea of what their cardiorespiratory fitness is they may decide that it needs to be improved to become a more competitive runner. In order to improve VO₂ Max the cardiorespiratory system must be adequately taxed. This is a much easier task in the novice than in the elite runner.

The following scale may be useful to determine training intensity:5

Very Light to Fairly Light: 25-44% VO₂ Max
Fairly Light to Somewhat Hard: 45-59% VO₂ Max | Notice breathing deeper but conversation possible |
Somewhat Hard to Hard: 60-84% VO₂ Max | More difficult to hold conversation |
Very hard: 85% VO₂ Max | Harder breathing and becoming uncomfortable don’t want to talk |
Maximal: 100% VO₂

Novice Runners 6,7,8
Training at intensities that are considered “moderate” in intensity (40-50%VO₂ Max) could be useful to increase maximum aerobic capacity.

Intermediate Runners 8
Training at intensities that are considered “hard” 60-80% of  VO₂ Max will likely enhance maximum aerobic capacity. There is potential that runners who training <60-80 km a week may be able to improve VO₂ Max by increasing training load.  Some low volume training at VO₂ Max may be beneficial.

Well Trained Runners
In well trained runners training at or near VO₂ Max is probably optimal. This type of training can be stressful and should be periodized and is not appropriate for everyday runs. A sample periodized training plan has been proposed by Midgley et al.

  • Perform several months of base training at 65-70% VO₂Max
  • A transition phase of around 85% VO₂ Max would then be implemented
  • Targeted VO₂ Max training would begin after base training and the transition phase

Midgley et al. suggests that the targeted VO₂ Max training increase in intensity from midway between velocity at lactate threshold (vLT) and vVO₂ Max then eventually progress training to levels that exceeds vVO₂ Max. I have described how to estimate the velocity at lactate threshold in another article and how to estimate vVO₂ Max in the testing section of this article.

Training at or close to vVO₂ Max can typically only be sustained for ~6 minutes so interval training may be valuable to increase the actual time at vVO₂ Max during a training session. 

Elite runners may need to assess whether they even need to try to improve VO₂ Max. Many of these runners may have hit their ceiling after many years of training.

Bottom Line
Maximum aerobic capacity is associated with running performance and can be trained. As a runner becomes progressively more experienced increased training intensity will likely need to be employed. Care must be taken not to over train.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. Midgley, Adrian W., Lars R. McNaughton, and Andrew M. Jones. “Training to enhance the physiological determinants of long-distance running performance.”Sports Medicine 37.10 (2007): 857-880.
2. Physiological Testing of the High-Performance Athlete
3. O’GORMAN, D. O. N. A. L., et al. “Validity of field tests for evaluating endurance capacity in competitive and international-level sports participants.”The Journal of Strength & Conditioning Research 14.1 (2000): 62-67.
4.  Léger, L., and D. Mercier. “Gross energy cost of horizontal treadmill and track running.” Sports medicine 1.4 (1984): 270-277.The gold standard measure of cardiorespiratory fitness is called maximum aerobic capacity or VO2 max.
5. http://www.move.va.gov/download/Resources/CHPPM_How_To_Write_And_Exercise_Prescription.pdf
6. Branch, J. David, Russell R. Pate, and Sharon P. Bourque. “Moderate intensity exercise training improves cardiorespiratory fitness in women.” Journal of women’s health & gender-based medicine 9.1 (2000): 65-73.
7.Poole, David Christopher, and GLENN A. GAESSER. Response of ventilatory and lactate thresholds to continuous and interval training. MS thesis. UCLA, 1984.
8. Midgley, Adrian W., Lars R. McNaughton, and Michael Wilkinson. “Is there an Optimal Training Intensity for Enhancing the Maximal Oxygen Uptake of Distance Runners?.” Sports Medicine 36.2 (2006): 117-132.

 

Running: Lactate Threshold

Posted on 01.12.14

__
Lactate is a product of energy metabolism and can also serve as a fuel source. It is present in the blood stream during rest and increases as a person incrementally transitions from walking, then jogging, and progressively faster running speeds. There becomes a point when the runner will begin to produce lactate quicker than will diffuse from the blood.  This is referred to as the lactate threshold. Once this threshold is reached the concentration of lactate in the blood rises sharply and is associated with fatigue and exhaustion.

Why is the Lactate Threshold Important?Cross Country

  • Lactate threshold has been shown to be superior to maximum oxygen uptake (Vo2 max) when assessing endurance performance (homogeneous groups).
  • There is a strong correlation between lactate threshold and endurance running performance.
  • If a runner is able to run at a greater speed before reaching lactate threshold they should be able to hold a faster race pace before fatigue.

How can Lactate Threshold be determined?

Lab testing would be the gold standard but several field tests have been proposed.  One field test that has been shown to be fairly accurate in ccompetitivedistance runners and triathletes is the 30 minute time trial.  Both heart rate and running velocity at the lactate threshold can be accurately obtained. As a general reference if training feels “somewhat hard” then the runner is probably running at the lactate threshold. Training just above lactate threshold would be consider “hard” to “very hard”.

30 Minute Time Trial

Equipment: Treadmill, Heart Rate Monitor, Something to cover distance and possibly time on dash board

Methods

  • Cover indicators of kilometers per hour
  • Perform a self selected warm-up
  • Set the treadmill to a 1% grade
  • Gradually increase running speed to a self-selected pace that would be sustained for 30 minutes
  • Once at the self selected 30 minute race pace the trial begins
  • Running speed can be adjusted at any time
  • If somebody is helping administer the test the runner should be told the time every 5 minutes (if administering alone an uncovered timer on the treadmill should be acceptable)
  • Heart rate is taken every 5 minutes
  • The runner should NOT BE AWARE of the distance covered until the end of the test

Once the test is completed the distance covered in kilometers(km) should be divided by o.5 hours (h).  This is the average running velocity (km/h) and can be used as an estimate of the lactate threshold.  The average heart rate taken during the final 20 minutes can be used to estimate the heart rate at lactate threshold.

Training to improve lactate threshold

It is common for runners to train with intervals or continuously at or above their lactate threshold to affect improvements in endurance performance. The following is a modification of a long interval training program that has been demonstrated to improve lactate threshold and time to exhaustion in less well trained and some well trained endurance athletes.  It is  adapted from Demarle et al., 2003.

Sample Program

Calculate running velocity (km/h) at lactate threshold using 30 minute time trial.  Once this is determined the intensity of the long intervals can be calculated.

1. Calculate velocity (intensity) of intervals: Both the intense and rest intervals will need to be calculated.

  • Intense Interval=Velocity at Lactate Threshold+1km/h (e.g. 16km/h+1km/h=17km/h)
  • Rest Interval= 0.55 X velocity lactate interval (e.g 17 km/h X 0.55=9 km/h)

So, if a runner’s velocity at lactate threshold is 16 km/h then simply add 1km/h and this determines how fast to run for the interval.  Once the calculation for the intense interval is completed the “rest” interval would be approximately 1/2 of the speed of the intense interval.

2. Intervals Intervals would alternate high and low intensity. Higher intensity intervals would be run at:

  • 5 minutes for less well trained runners
  • 6 minutes for highly trained runners

Lower intensity/rest intervals would be run at:

  • 2.5 minutes for less well trained runner
  • 3 minutes for highly trained runners

One Full Interval Would=High Intensity+Rest Interval

3. Weekly Training Less well trained individuals would train as follows 2 times a week for 4 weeks.

_____________Week 1______Week 2______Week 3______Week 4
1st session     4 Intervals      3 Intervals      4 Intervals      5 Intervals
2nd session    3 Intervals      4 Intervals      5 Intervals      8 Intervals

Trained individuals would train as follows 2 times a week for 8 weeks.

_____________Week 1______Week 2______Week 3______Week 4
1st session     4 Intervals      3 Intervals      3 Intervals      3 Intervals
2nd session    2 Intervals      2 Intervals      2 Intervals      6 Intervals

_____________Week 5______Week 6______Week 7______Week 8
1st session     4 Intervals      4 Intervals      4 Intervals      4 Intervals
2nd session    5 Intervals      5 Intervals      5 Intervals      5 Intervals

Program Expectations

Less well trained individuals can expect to improve their velocity at lactate threshold and subsequent time to exhaustion with this program. From the study this was adapted, 1/2 of the well trained individuals demonstrated improvement in velocity at lactate threshold performing this protocol 2 x’s a week.  Experienced runners that do not perform higher intensity training will likely benefit more than those who already incorporate higher intensity training.

Bottom Line

    • If a runner is able to run at a greater speed before reaching lactate threshold they should be able to hold a faster race pace before fatigue.
    • Training can improve lactate threshold.
    • Velocity and heart rate at lactate threshold can be accurately assessed with the 30 minute time trial.
    • 30 minute time trial can be used to test and re-test if training interventions are improving lactate threshold.
______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. Faude, Oliver, Wilfried Kindermann, and Tim Meyer. “Lactate threshold concepts.” Sports medicine 39.6 (2009): 469-490.
2.James C. McGehee1, Charles J. Tanner1, and Joseph A. Houmard, A Comparison of Methods for Estimating the Lactate Threshold Journal of Strength Conditioning Research, 2005 Aug;19(3):553-83. Péronnet, F. “Lactate as an end-product and fuel.” Deutsche Zeitschrift fur Sportmedizin 61.5 (2010): 112.
4. Demarle, A. P., et al. “Whichever the initial training status, any increase in velocity at lactate threshold appears as a major factor in improved time to exhaustion at the same severe velocity after training.” Archives of physiology and biochemistry 111.2 (2003): 167-176.
5. Scherr, Johannes, et al. “Associations between Borg’s rating of perceived exertion and physiological measures of exercise intensity.” European journal of applied physiology 113.1 (2013): 147-155.

Soccer: Strength Expectations

Posted on 01.3.14

_______
To be competitive in a sport such as soccer, the management of a number of fitness qualities is almost a necessity. One of these qualities is physical strength. Adequate strength serves as a foundation for injury prevention, and when developed  results in improved markers of athletic performance. Some of the improved markers of performance gained through strength training include: 1,2

  • Improved Sprint PerformanceWembley_Stadium_interior
  • Increased Vertical Jump Height
  • Improved Change of Direction

These are a few of the reasons that many soccer players wisely employ strength training.

Strength development takes time and is typically worked into a long term training plan. If the athlete is aiming to compete at a high level the physical strength that elite players possess may be reasonable long term goals.

What are reasonable strength expectations for high level soccer?

Calculations to determine reasonable strength expectations of elite adult male and female soccer players have been proposed.3 The following are the results of calculations for men weighing between 140-200 pounds and women between 100 and 180 pounds. The women’s calculations are less specific.

Bench Press and Squat Expectations for Men:

Body weight:  140 lbs.     Bench Press:  195 lbs.     Squat:  390 lbs.
Body weight:  150 lbs.     Bench Press:  205 lbs.     Squat:  410 lbs.
Body weight:  160 lbs      Bench Press:  215 lbs.     Squat:  430 lbs.
Body weight:  170 lbs.     Bench Press:  220 lbs.     Squat:  445 lbs.
Body weight:  180 lbs.     Bench Press:  230 lbs.     Squat:  460 lbs.
Body weight:  190 lbs.     Bench Press:  240 lbs.     Squat:  480 lbs
Body weight:  200 lbs.     Bench Press:  250 lbs.     Squat:  495 lbs

Bench Press and Squat Expectations for Women:

Body weight:  100 lbs.     Bench Press:  70-85 lbs.     Squat:  165-240 lbs.
Body weight:  110 lbs.     Bench Press:  70-85 lbs.     Squat:  175-255 lbs.
Body weight:  120 lbs.     Bench Press:  75-95 lbs.     Squat:  185-270 lbs.
Body weight:  130 lbs.     Bench Press:  80-100 lbs.   Squat:  196-284 lbs.
Body weight:  140 lbs.     Bench Press:  85-105 lbs.   Squat:  207-300 lbs.
Body weight:  150 lbs.     Bench Press:  90-110 lbs.   Squat:  215-313 lbs.
Body weight:  160 lbs.     Bench Press:  95-115 lbs.   Squat:  225-325 lbs.
Body weight:  170 lbs.     Bench Press:  95-120 lbs.   Squat:  235-340 lbs.
Body weight:  180 lbs.     Bench Press:  100-125 lbs. Squat:  244-355 lbs

The values given for the squat are for the half squat.  For details on the depth of the half squat please see: The Squat: An Introduction.

Bottom Line

Strength training for Soccer may be useful for improving performance.  Strength expectations of high level soccer players may serve as good long term strength goals for competitive players.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. Wisløff, U., et al. “Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players.” British journal of sports medicine 38.3 (2004): 285-288.The 
2.  Keiner, M., et al. “Long term strength training effects on change-of-direction sprint performance.” Journal of strength and conditioning research/National Strength & Conditioning Association (2013). 
3. Stølen, Tomas, et al. “Physiology of soccer.” Sports medicine 35.6 (2005): 501-536.

Strength Qualities

Posted on 11.6.13

_______
Intelligently designed programs based on traditional strength and power training result in improved markers of performance.  However, there are more specific pieces to the strength puzzle, and in many cases more decisions to be made. Performance gains may be further enhanced by purposefully addressing specific qualities of strength, particularly in more advanced athletes.

Strength Qualities

The strength qualities described in this article are specific to performance requiring one to a few maximum efforts. Example are, the shot put, long jump and individual portions of activities that last longer, such as the sprint.

Jessica_Ennis_-_long_jump_-_1 (1)While there are other strength qualities and different ways of describing them, we intend to focus on the six measurable qualities described by Newton and Dugen.1 I believe that considering these six strength variables enhances program design. Although higher-level athletes tend be ideal for program design involving specific strength qualities, this does not mean the rehabilitation patient confined to a wheelchair cannot also benefit.

1. Maximum Strength-  This is the maximum amount of force that can be generated during a relatively “slow” voluntary muscular contraction.  Think of traditional resistance training. Typically high levels of force are generated but not a great deal of speed. A 1-repetition maximum (RM) in the deadlift, squat or bench press would be a display of maximal strength.

This is important because we know maximum strength is associated with markers of athletic performance.

As an example, in the recreational athlete ~23% change in squat 1 RM  results in a significant increase in sprint time.2 This association between improvement in squat strength 1 RM and sprint performance indicates that maximum strength may be an important quality in recreational athletes.

Decision Making:  If a recreational athlete wishes to increase sprint speed, then working to improve maximum strength may be of benefit.

2. High-Load Speed-Strength- High-load speed-strength is the highest force that can be produced as quickly as possibly using relatively heavy loads (>30% of maximum effort). A perfect example would be a javelin thrower performing 30%to 100% of their 1 RM in the power clean. The power clean is a good representation of high-load speed strength as it can be loaded up to 100% of the athlete’s 1 RM.

Kari Ihalainen who is the national Korean javelin coach, compiled data of strength norms among varying levels of javelin throwers.  His data demonstrate that an increase in the power clean 1 RM among other lifts is associated with a distance improvement in the javelin throw. Women who power clean  ~ 130 pounds tend to throw ~ 130 feet and those that clean ~250 pounds tend to throw ~ 240 feet.3 This association seems to indicate that high-load speed-strength is an important attribute for javelin throwers to develop.

Decision Making:  Based on data of strength norms among female javelin throwers, greater levels of high-load speed-strength (among other strength qualities) seem to be associated with increased javelin throw distance. If a national-level javelin thrower’s power clean is relatively weak, perhaps improving this high-load speed strength lift will result in improved performance.

3. Low-Load Speed Strength- Low-load speed strength is the highest force that can be produced as quickly as possible using relatively light loads (<30% of maximum effort). The shot put event is a demonstration of low-load speed strength.  Putting a shot of varying weights or performing light bench press throws are options to improve low-load speed strength in the upper body.

Decision Making:  If distance in the shot put continues to improve with implement training and low-load speed strength exercises, then that athlete should probably continue focusing on training this strength quality. If shot distance is plateauing, then the athlete will likely need to look closely at other strength qualities that may have weak points such as maximal strength.

4. Rate of Force Development (RFD)- This is the development of maximal force in minimal time.5  Think of muscular force that is generated during the initiation of a movement (0-200ms).4 The more rapidly force increases, the quicker you will be able to get out of a chair or lift an object or your body from the ground.

There is a correlation between vertical jump performance and RFD.5 A high jumper working on increasing vertical jump height might want to work on training that improves RFD.  This type of training may involve heavy explosive strength training and cueing to lift “fast”.6,7

Decision Making: A high jumper looking to increase RFD may want to focus on heavy explosive weight training. This means weights >85% of 1 RM ~ 5 repetition sets and longer rest periods. Repetitions would be performed fast.

High jumpers tend to be rather slender. The jumper must be mindful not to add unnecessary muscle size. In theory, training with low repetitions in an explosive manner should not create excessive hypertrophy in most people.

5. Reactive Strength-  The ability to change direction from a lengthening muscle contraction (eccentric) to a rapid shortening muscle contraction (concentric). Reactive strength is important for sports such as basketball that requires players to change direction often.

A good way to generically assess reactive strength of the lower body would be to compare vertical jump performance to the depth jump. Somebody with reasonably good reactive strength should have a depth jump that is higher than his or her vertical jump.1 Be mindful that the depth jump is not appropriate for everyone and a coach or exercise professional should be consulted to determine if it if suitable for the individual.

Decision Making:  If the depth jump is not higher than the vertical jump then reactive strength may be lacking.  Plyometric exercise including the depth jump may be helpful for improving reactive strength.

6. Skill Performance-  This is the ability of the motor control system to put together the other five strength qualities, and it can be assessed by actually performing the skill e.g. shot-put/high jump.

Decision Making:  Analyze skill performance and attempt to distinguish which strength quality may need fine tuning to improve performance.

Bottom Line
There is more to performance preparation than just generic strength and power training.  Strength qualities such as the six described in this article can be important for  improving performance of activities requiring one or a few maximum efforts.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. Newton, Robert U., and Eric Dugan. “Application of strength diagnosis.”Strength & Conditioning Journal 24.5 (2002): 50-59.4. McBride, Jeffrey M., et al. “Relationship between maximal squat strength and five, ten, and forty yard sprint times.” The Journal of Strength & Conditioning Research 23.6 (2009): 1633-1636.
2.Cronin, John, et al. “Does Increasing Maximal Strength Improve Sprint Running Performance?.” Strength & Conditioning Journal 29.3 (2007): 86-95.-95.
3. http://www.speerschule.ch/docs/doc_ihal-tabellen.pdf (accessed 11/06/2013)
4.Aagaard, Per, et al. “Increased rate of force development and neural drive of human skeletal muscle following resistance training.” Journal of applied physiology 93.4 (2002): 1318-1326.7. McLellan, Christopher P., Dale I. Lovell, and
5.Gregory C. Gass. “The role of rate of force development on vertical jump performance.” The Journal of Strength & Conditioning Research 25.2 (2011): 379-385.5. Sahaly, R., et al.
6.”Maximal voluntary force and rate of force development in humans–importance of instruction.” European journal of applied physiology85.3-4 (2001): 345-350.
7. Heggelund, Jørn, et al. “Maximal strength training improves work economy, rate of force development and maximal strength more than conventional strength training.” European journal of applied physiology (2013): 1-9.

Running Economy

Posted on 10.23.13

_______
With all things being equal those with good running economy use less energy and less oxygen than those with poor economy. The runner that requires less oxygen will perceive running to be easier and will be able to run at a faster pace before feeling fatigue. Even small improvements in running economy can have profound effects on performance.1,2

The purpose of this article is to introduce the reader to running economy and how it may be trained.
_______

What is running economy?

runnersRunning economy comes down to how much energy a runner needs to run at a certain velocity (miles/kilometers per hour).3 Think of the energy cost a cross-country runner expends running at a fixed pace during a race.

All things being equal, a more economical runner will use less oxygen, perceive less difficulty running, and expend less energy.

Several factors can influence running economy including:

Physiology:  When we run our heart rate, respiration rate and body temperature increase, and we begin to sweat and become fatigued. All of these factors may be associated with running economy and come with a metabolic price tag in the form of expended energy.3 

In theory, a runner considered to have good running economy would compete with a comparatively lower heart rate, efficiently regulated body temperature, and slower accumulation of blood lactate. Steep increases in blood lactate are associated with fatigue.

Muscle fiber type also plays a physiological role in running economy. It is thought a greater proportion of slow twitch muscle fibers are positively associated with running economy.3 Slow twitch muscle fibers are efficient at utilizing oxygen.

Biomechanics: Efficient or skillful use of the body uses less energy and may improve running economy. For example, moving the arms excessively would decrease economy.

Some modifiable and non-modifiable biomechanical factors that are positively related to running economy include:3

  • Lean body type
  • Average to slightly shorter height for men
  • Slightly taller height for women
  • Leg mass distributed more in the hips
  • Narrow pelvis and smaller than average feet
  • Stride length, which the individual has adopted over time (aerobic demand is lower at self-selected speed)
  • Well-cushioned and light-weight shoes
  • Decreased vertical motion (not a lot of up and down motion, which effectively wases energy)
  • Rear foot striking (during a rear foot strike, footwear/skeletal structure takes load, as opposed to musculature, which requires more oxygen)
  • Stiffer muscles resulting in more stored elastic energy (good co-activation of muscles around knee and ankle joints)

_______

Training to Improve Running Economy

Specificity of training seems to influence running economy. In a study of 800/1500 meter elite runners and marathoners, the 800/1500 meter runners were more economical at faster speeds (11m/h).5 The marathon runners were more economical at slower speeds.

If you want to be more economical at slower speeds, training like a marathon runner might be optimal while training like a middle-distance runner may be more beneficial for increasing economy at faster speeds.

Strength/Power Training

Both strength training and power training positively influence running economy. As the muscles get stronger, co-contract better, and become more powerful, they become more efficient at storing and transferring energy. This theoretically should help decrease energy expenditure of the skeletal muscles.

I have given an example of a strength training program shown to improve running economy in triathletes in another article titled Distance Running & Strength Training. Power training with a focus on jump training has also been shown to be beneficial for runners wishing to improve economy.

The following is a sample power training workout adapted from Turner et al. that was shown to improve running economy in moderately trained runners.6 The runners were “apparently healthy” and performed power/jump training three days a week for six weeks concurrently with their regular running regimen. Each session consisted of six exercises:

  • Running TrackWarm-up vertical Jump – Performed continuously at 50% of maximum vertical jump effort.
  • Vertical Jumps (Double Leg) – Jump maximally and rest in between jump attempts.
  • Vertical Jumps (Single Leg) – Jump maximally with one leg and land with 2 legs.  Rest between attempts.
  • Springing Vertical Jumps – Continuous 6-8 inch vertical jumps, springing from the calves with decreased emphasis on hip and knee action.
  • Split Squat Jumps – Maximum split squat efforts repeated continuously.
  • Incline Jumps – Performed the same way as the springing vertical jumps, but up a hill with a 6-8% gradient.  The balls of the feet make iniital contact, then spring up when the heel makes contact.

Repetitions by week:

  • Warm-up vertical jump – Week 1-6 perform 10 repetitions (reps)
  • Vertical Jumps (Double Leg) – Week 1-5 reps, Week 2-8 reps, Week 3-10 reps, Week 4- 12, Week 5-15, Week 6-15
  • Vertical Jumps (Single Leg) – Week 1-5 reps each leg, Week 2- 5 reps, Week 3-8, Week 4 -8, Week 5-10, Week 6-10
  • Springing Vertical Jumps – Week 1-15, Week 2-20, Week 3-25, Week 4-25, Week 5-30, Week 6-30
  • Split Squat Jumps – Week 1-5 each leg, Week 2-8, Week 3-10, Week 4-15, Week 5-20, Week 6-20
  • Incline Jumps – Week 1-10, Week 2-15, Week 3-15, Week 4-20, Week 5-25, Week 6-25

Both strength and power training have a positive influence on running economy.

Altitude Exposure  (Live High,Train Low)

Athletes wishing to improve running economy may choose to live at higher altitudes and train/compete at sea level to improve performance.7 The reasoning is that physiological changes, such as increased red blood cell mass, will positively affect performance when an athlete competes at a lower elevation. Becoming acclimated to higher altitudes allows for improved oxygen delivery and utilization, which should improve running economy.3

For those who cannot live at higher altitudes and train at lower altitudes, normoberic hypoxic apartments, supplemental oxygen, and hypoxic sleep devices may be used.

Training in The Heat

Once a person acclimatesto training in warm conditions, blood plasma volume can improve up to 12%, resulting in less work for the heart.3 Heat-acclimated runners may also benefit from lower heart rate and core body temperature.3 These physiological changes are associated with improved running economy and lend support to the idea of training in warm conditions.

Bottom Line

Several forms of training, including traditional endurance work, strength/power training, altitude exposure. and training in warmer conditions may result in improvements in running economy.  These may be worthwhile training strategies as even small improvements in running economy can have profound effects on performance.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. Karp, Jason R. “An In-Depth Look At Running Economy.” Track Coach 182 (2008): 5801-5806.
2. Jung, Alan P. “The impact of resistance training on distance running performance.” Sports Medicine 33.7 (2003): 539-552.
3. Saunders, Philo U., et al. “Factors affecting running economy in trained distance runners.” Sports Medicine 34.7 (2004): 465-485.
4.  Thomas, David Q., et al. “Changes in running economy and mechanics during a submaximal 5-km run.” The Journal of Strength & Conditioning Research 9.3 (1995): 170-175.Working to condition the body to perform with a
5. Daniels, J. A. C. K., and N. A. N. C. Y. Daniels. “Running economy of elite male and elite female runners.” Medicine and science in sports and exercise24.4 (1992): 483.A runner with good running economy will utilize less energy and in turn less oxygen than a less efficient runner.
6. Turner, Amanda M., Matt Owings, and James A. Schwane. “Improvement in running economy after 6 weeks of plyometric training.” The Journal of Strength & Conditioning Research 17.1 (2003): 60-67.6. Wilber, Randall L.
7. “Current trends in altitude training.” Sports Medicine 31.4 (2001): 249-265.Physiological Component

 

Power Training (An Introduction)

Posted on 10.9.13

_______
All of us need “enough” power to sufficiently perform the tasks we need or want to perform. To carry out these tasks some of us need to physically express more power than others.  Athletes are prime examples of those who must often perform movements in a very powerful manner.  This article focuses on power and how it relates to those who need to express high levels of power.

What activities would be classified as “high powered”? Classic examples include sprinting, jumping, Olympic lifting, and throwing.

The Basics
A greater ability to generate maximum pRugby Jumpower typically results in improved athletic performance.1 Given this fact, training to improve power production should translate into improved markers of athletic performance.

The goal of power training is typically to increase the amount of force produced over the shortest possible time.  Power output improves when the trainee is able to perform more work over the same amount of time or the same amount of work over a shorter period of time.2

                   power = force x velocity = work/time

_______

Common Modes of Power Training

Traditional Strength Training
Improving maximum strength, which tends to be the goal of traditional strength training, has been shown to improve power performance.3 This makes sense, given that traditional strength training results in improved force development (the ability to lift more weight).  Fundamentally, an individual cannot attain a high level of power output without being relatively strong.1

In most instances traditional strength training tends to be more than sufficient in allowing non-athletes or casual athletes the level of power output needed to accomplish their goals.  As a strength trainer becomes more advanced, he/she may wish to concentrate on performing strength movements quicker to maintain or improve power output.

Ballistic Resistance Exercise
A potential issue with traditional free-weight strength training is that even if a lift is performed quickly, the bar decelerates toward the end of the motion.  This inherent deceleration is why experts tend to recommend ballistic movements to improve power.1 Ballistic exercises such as bench press throws and jump squats allow for continued acceleration throughout the movement as well as greater velocity, force, power, and muscle activation 1.

It is also important to take note that ballistic lifts tend to be more sport specific than traditional weight-training counterparts.  For instance, a jump squat is more similar to a basketball dunk than a squat.

Olympic Lifts/Variations
Olympic lifts such as the snatch, clean and jerk, and variations such as the power clean allow for high velocity and force outputs.  There is a relationship between the power output during Olympic lifts and sprinting/jump performance.1 This relationship may allow for the transfer of training effects between Olympic lifts and sprint time and jump performance.  This transference has been demonstrated in previously untrained men who significantly improved both sprint time and jumping ability.5

Another benefit of Olympic lifting is that the athlete can train with heavy weight.  This allows the athlete to quickly move heavy loads, which may be beneficial to American football linemen and wrestlers.

Plyometrics
Plyometrics consist of exercises such as the depth jump.  When incorporated into a training program they can be effective at improving power in sport.  I will eventually touch on plyometrics in another article.

Optimal Loading of Exercises
“Optimal” load would be the load associated with maximum power production for that specific movement.1 The following is a list of exercises and the percentage of weight associated with maximum power production for that lift.  These are not set in stone and can vary, depending on training status, but may be useful to guide training.

  • Jump squat: 0% 1 RM of the squat
  • Bench Press Throw: 30-45% of Bench Press 1 RM
  • Clean/Snatch: 70-80% of 1 RM

To determine the appropriate resistance, a one-repetition max (1RM) would need to be determined and then a percentage taken.  For example, if you are able to bench press 100 lbs for a max effort and 30% was the optimal load of the bench press throw, then you would want to train with 30 lbs to maximize power production.1 It would be inappropriate to take the 1 RM of the actual bench press throw exercise due to the ballistic nature of the exercise and risk of injury.

General Training Parameters2

Loading-  Light loads are recommended for power-training; these equate to 0-60% 1RM for lower body exercises, 30-60% 1-RM for upper body exercise and 70-80% 1RM for Olympic lifts.
Volume- 1-3 sets per exercise utilizing 1-6 repetitions.  Repetition speed should be fast.
Rest Periods- 2-3 minutes between sets
Frequency- Typically periodized and structured into a strength-training program. Power training may be performed 2-5 days a week.

Sample Program
This is a sample of a power-training program that highlights the benefits jump squats can have on experienced resistance trainers.5

The participants trained twice a week for 10 weeks utilizing the jump squat.  The weight used was ~30% of the participant’s 1 RM of the squat.  Participants performed 3-6 sets of 6-10 repetitions, with a 3 minute rest interval between sets.

The training resulted in significant improvements in vertical jump and peak power during cycling.  Those assigned to the jump squat group outperformed a traditional strength-training (back squats) and plyometric group (depth jumps) in the vertical jump.

How to use this Information
Power can be improved through traditional strength training, but those requiring a greater ability to produce power may be served by specific power training.  Ballistic exercises, Olympic lifts/variations, and plyometrics are common ways to improve power production.  There are many training variables that can be manipulated, depending on the individual’s goals. Power training can complement and overlap both strength training and hypertrophy training styles.

I consider plyometrics and ballistic resistance training to be advanced techniques.  These movements tend to require assessment and instruction from an exercise professional.

______________________________________________________________________________________________________________

Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. Cormie, Prue, Michael R. McGuigan, and Robert U. Newton. “Developing maximal neuromuscular power.” Sports medicine 41.1 (2011): 17-38.
2 ”American College of Sports Medicine position stand. Progression models in resistance training for healthy adults.” Medicine & Science in Sports & Exercise. 41(3):687-708, March 2009.
3. Newton RU, Kraemer WJ. Developing explosive muscular power: implications for a mixed method training strategy. Strength Cond J 1994; 16 (5): 20-31
4. Tricoli V, Lamas L, Carnevale R, et al. Short-term effects on lower-body functional power development: weightlifting vs. vertical jump training programs. J Strength Cond Res 2005; 19 (2): 433-7
5. Wilson, Gregory John, et al. “The optimal training load for the development of dynamic athletic performance.” Medicine and Science in Sports and Exercise25.11 (1993): 1279.

Strength Training (An Introduction)

Posted on 09.14.13

_______
We all need to be strong enough to optimize the performance of activities we enjoy. The level of strength an individual requires can vary widely, from lifting groceries to dunking a basketball.  The focus of this article is not to review the health benefits of strength training but to introduce the reader to strength training as it relates to performance.  So, what can be expected from a strength-training program?

An appropriately designed strength training program can result in: 1,2

  • Improved strength, power, speed, acceleration, and running economy (how efficiently a runner utilizes resources such as, oxygen)
  • Increased vertical jump height
  • Muscular hypertrophy (increased muscle size)

How Do We Get Stronger?

When our bodies are subjected to sufficient amounts of resistance, they will adapt and become stronger.  During the initial phases of a strength program, gains are due primarily to the nervous system becoming more efficient.3  Our nervous system gets better at activating muscle fibers that need to be called upon and decreasing the activation of muscle fibers that hinder the desired movement.  This results in a net improvement in strength.

Hercules

When starting a strength-training program we also get better at performing strength movements.  Practicing movements such as the squat allows us to learn how to detect where the body is in space and to exploit the best biomechanical positions that allow the best expression of strength.3 Learning how to optimize the performance of strength movements allows us to lift more.

Aside from the initial neurological adaptations that are expected from weight training, we eventually begin to realize hypertrophic changes of the muscles.  As the size of the muscle increases, the ability to produce muscle force also increases.4

Frequency 

Evidence suggests that the best way for a beginner to increase strength is to train each major muscle group 3x’s a week.5 When deciding on training frequency it is important to keep in mind that each exercise session can affect the subsequent session.

Optimal training frequency can vary depending on the individual’s ability to recover and factors such as volume and intensity of training sessions.  After working a major muscle group, we recommend 48 to 72 hours of recovery before working that muscle group again.  Support for waiting at least 48 hours has been demonstrated in a study of novice female resistance trainers who had not fully recovered (94%) their lower body strength two days after a lower body workout.6

In the case of the advanced trainee/athlete evidence suggests that training up to 6x’s a week is acceptable but training each major muscle group only 2x’s a week seems to result in the greatest strength gains 7.  Training each major muscle group 2x’s a week over 6 sessions is possible when employing a split routine e.g. arms trained on one day, chest on another etc..

Intensity

Training with as little as 60% of a 1 repetition max (1RM) or ~15 repetitions is sufficient to maximize strength gains in the beginner.4,5,7 Performing 8-12 repetitions when 15 could be performed may be recommended.  The beginner would perform an “easy” 8-12 repetitions for his or her sets.

In order to maximize strength in more advanced trainees utilizing 85% of 1- repetition max (1RM) or 5-6 repetitions is advisable.7 While these repetition ranges seem to optimize strength gains, a variety of rep ranges may need to be used to maximize strength.

Sets

For beginners, the optimal number of sets during a training session seems to be 4 per muscle group and up to 8 for advanced trainees.5,7 Be mindful that the untrained individual may time to adapt to multiple set training, and much of the benefit from the sets and reps may be from learning the strength movements.

Exercise Selection

Both multi-joint and single-joint exercises are effective for gaining strength.  Multi-joint exercises such as the squat, bench press and deadlift are generally regarded as the best choices for overall strength.6 Single-joint exercises such as the knee extension are also effective strength builders, as are cables, bands, and other strength-training accessories.

Rest Interval

When developing strength, rest intervals of 3-5 minutes allow for less performance decrements than shorter rest intervals.6 In theory, this would allow the resistance trainer the ability to handle heavier weights during subsequent sets, resulting in greater strength gains.

Muscular Failure

Training to muscular failure is training to a point at which the strength trainer is no longer able to lift a load. As an example, an individual may be able to lift five reps but can’t get the sixth, and a spotter must help.  This type of training is probably good to use in moderation. When training to failure, more muscle fibers may be stimulated, leading to greater strength gains.

Repetition Speed

Moderate to slow repetition speed is recommended; however, as the strength trainer becomes more advanced a variety of speeds may be utilized.4

Repetition speed should be dependent on the individual’s. When working on a strength quality such as speed-strength (power,fast strength) repetition speed would be faster.

Example of a Beginner Workout

Bench Press 2-4 x 8-12 repetitions (controlled rep speed)
Deadlift 2-4 x 8-12 repetitions (controlled rep speed)
Back Squat 2-4 x 8-12 repetitions (controlled rep speed)

Example of an Advanced Split Routine Workout (Chest Focus)

Incline Bench Press 2×5 repetition max
Weighted Dip Machine 2×5 repetition max
Bench Press 2×5 repetition max

Certain aspects of a strength program will need to be manipulated to maximize strength. Aspects of manipulating volume/intensity are touched on in an introduction to periodization.

How to use this Information

Strength building is important for those wishing to improve performance for a wide variety of activities.  The information presented is meant to outline aspects of a basic strength training program.  There are many training variables that can be manipulated, depending on the individual’s goals.  Strength training complements and overlaps both hypertrophy training and power-training styles.

______________________________________________________________________________________________________________
Author: Christopher (C.J.) Eberley, PT, DPT
Board Certified Orthopedic Physical Therapist
_______
Disclaimer: The views discussed on this website are for educational purposes only. Should you have any questions please consult your physician or physical therapist. Copyright© Kinesis Physical Therapy. All Rights Reserved.
_______

References

1. McGuigan, Michael R., Glenn A. Wright, and Steven J. Fleck. “Strength training for athletes: does it really help sports performance?.” International journal of sports physiology and performance 7.1 (2012): 2.
2. Paavolainen, Leena, et al. “Explosive-strength training improves 5-km running time by improving running economy and muscle power.” Journal of Applied Physiology 86.5 (1999): 1527-1533.
3.Haug, William B. “Predictors in Strength Gains in Untrained Men Over 9 Months of Training.” (2011).
4.”American College of Sports Medicine position stand. Progression models in resistance training for healthy adults.” Medicine & Science in Sports & Exercise. 41(3):687-708, March 2009.
5. Rhea, Matthew R., et al. “A meta-analysis to determine the dose response for strength development.” Medicine and science in sports and exercise 35.3 (2003): 456-464.3.
6. Kraemer, WILLIAM J., and NICHOLAS A. Ratamess. “Fundamentals of resistance training: progression and exercise prescription.” Medicine and science in sports and exercise 36.4 (2004): 674-688.
7. Peterson, Mark D., Matthew R. Rhea, and Brent A. Alvar. “Maximizing strength development in athletes: a meta-analysis to determine the dose-response relationship.” The Journal of Strength & Conditioning Research 18.2 (2004): 377-382.
  • 1
  • 2
  • Next Page »

Categories

  • Body Composition
  • Flexibility
  • Performance
  • Power
  • Self Assessment
  • Strength
  • Wellness

Recent Articles

  • Heritability & Physical Performance
  • Heritability & Physical Performance
  • Case Study: General Strength Improvement
  • Resistance Training Periodization: An Introduction
  • Repeated Sprint Ability: An Introduction

Kinesis Physical Therapy, LLC. All Rights Reserved