Figure 1: (Left Graph) relationship between load and percentage of 1rm. (Right Graph) An example of a force-time curve depicting how different elementary qualities are expressed with different external loads. Graphs are modified from “supertraining”
Explosive strength is not an independent quality, meaning there is no specific exercise that directly trains all of the components involved in its production. Instead, it is comprised up of four “elementary qualities” (listed below and in figure 1). These elementary qualities are independent of each other and must be developed through separate means. Together, they form the expression of explosive strength.
Maximal Velocity (Vo)
Starting Strength (early stage rate of force development) (SS)
Acceleration Strength (late stage rate of force development) (AS)
Maximal Strength (So)
The role of each of these qualities change depending on the athlete’s sport and level of development.
It should be noted that maximal strength and acceleration strength are deemed the two “easiest” qualities to improve. It is not until in the later stages of development that maximal velocity and starting strength become of greater significance. However, their exact level of importance, in regards to expressing explosive strength, is dependent on the loads encountered in sport
max velocity will always play a larger role for a javelin thrower than it would for a powerlifter
Not all of these qualities can be targeted using a single exercise modality. For example, any sort of non-ballistic back squat will never reach the same mean and peak velocity compared to that of a ballistic jump squat. Instead of thinking in terms of load percentages, it might be best to think in terms of velocity, power, and force. This way, you wont have to try and make the exercise modality fit the emphasis, you let the emphasis dictate the exercise modality.
Below are some examples of how to improve specific qualities within the two-foot, starting from a static position, jumping pattern
Heavy Squats (85-100% 1rm)
Banded back squats with 50% bar weight and 20% band weight, or 50-60% 1rm trap bar jumps.
The best way to understand acceleration strength is to think of it in terms of “how fast can I get the bar moving after I have already got it started moving?”. Acceleration strength doesn’t always imply “Faster is better”, but instead it means you are actively accelerating the bar in a dynamic fashion throughout the entire movement. This is why bands and heavy jumps are good tools. Rapid force development is required throughout the whole movement and not just the early stages
Static start weighted vest jumps with 0-20% BW.
The goal is to focus on the initial explosion through beginning stages of the movement. Unlike acceleration strength, the later stages of the movement should be dominated by the momentum you built up from the initial burst.
Band assisted squat jumps ranges from BW to -20% BW
The goal here is to use submaximal loading (reduced body weight) to induce supramaximal speeds. It is important to note that the bands are not “pulling” me up. Instead, the bands act as a way for me to counteract gravity and reduce my body weight.
The specific need of each elementary quality will vary depending on the external load imposed upon the athlete (Figure 1). In short, there are typically three types actions we see in sport.
- The first is where the athlete has to produce power and transfer it into an external object.
- The second is where the athlete has to produce power relative to their own body weight.
- The third is where the athlete has to do some combination of actions 1 and 2.
Depending on which actions are required, the role of each elementary quality will vary. Thus, understanding the external loads imposed upon the athlete will dictate the importance of each quality.