Running Economy

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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.
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What is running economy?

Running 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)

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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:

• Warm-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.

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