Power is an important component of an athlete's abilities. Defined as the rate at which mechanical work is performed, understanding the point of fatigue for different intensities is important. Researchers at the University of Salford in the UK set up a small study which examined the optimal load intensity for athletes to perform extra repetitions before the effects of muscle fatigue set in.
It is known that the optimal power load for static squat jumps is lower than loads recommended for power training. This study looked at the effect of 4 different loads on point of fatigue during the squat jump.
17 subjects were recruited to participate in the study. They were all adult males and professional rugby league players. They performed experimental sets of 6 repetitions at 0% 1RM, 20% 1RM, 40% 1RM or at 60%1RM.
-Dont forget to bookmark Time to Fatigue When training Power with the Squat
There were no significant differences between the 0, 20 and 40% loads in terms of peak force, velocity, power or displacement. There was also no difference in the peak force for the 60% load.
The only differences, which were considered significant, occurred at the 60% 1 RM load intensity for the velocity measure, power measure and for the displacement. These readings were significantly lower on the 5th and 6th repetition compared to the 1st and 2nd, at 60% 1RM.
These findings show that training at 40%1RM or less for up to 6 repetitions would not elicit muscle fatigue. This intensity and volume allows the athlete to perform sets without going to fatigue. At 60% 1RM, athletes should be performing no more than 5 reps to maintain optimal speed, power and to minimise fatigue.
Thomasson, ML, Comfort, P. 2012. "Occurrence of fatigue during sets of static squat jumps performed at a variety of loads." Journal of strength and conditioning research. 26(3): 677-683.