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.
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.
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.
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.