The use of eccentric training for increasing strength or hypertrophy is not a new concept. It is thought that the added time under tension and increased muscle damage caused by eccentric emphasis during training will result in greater gains in muscle cross sectional area. Since individuals are able to lower more weight eccentrically than they can lift concentrically, it is thought that performing eccentrics with supramaximal loads (greater than 1RM) will yield increases in maximal strength (eccentric and concentric). What remains to be determined however, is the efficacy of eccentric training for improving athletic performance markers. If supramaximal eccentrics increase maximal strength (1RM), will that automatically carry over to athletic qualities such as rate of force development or maximal voluntary isometric contraction?
An ahead of print study published recently from the Journal of Strength and Conditioning Research evaluated the effects that supramaximal eccentric training had on maximal strength (Leg Press 1RM), maximal isometric strength (maximal voluntary contraction) and rate of force development (countermovement jump and squat jump). Fifteen recreationally active college students from the University’s Sports Science program were the chosen subjects. Strength and performance testing was performed before and after a 6 week training period. The subjects trained 3 days per week over the 6 weeks where they performed unilateral, supramaximal eccentrics on a 45-degree leg press. Subjects performed 5 sets of 3 reps with a 5 to 6-min rest between sets. Each rep was carefully monitored to ensure a 90-degree knee angle was achieved with each rep. Weight was added each week if the subjects could maintain a 3-second eccentric during the exercise. Post-testing showed that 1RM leg press increased significantly (31.1%). However, changes in rate of force development and maximal voluntary isometric contraction were non-significant.
The results of the current study suggest that supramaximal eccentric training may be suitable for increasing maximal strength. However, this method may not be a good method for improving rate of force development or maximal voluntary isometric force. This has important implications for strength coaches. It would be interesting to see if bilateral training would make any difference, or if more specific exercises (i.e., squats) would have an effect on the results. The researchers chose the leg press exercise and single-leg reps due to the high risk involved with the heavier loads required for bilateral supramaximal eccentrics. There is certainly a higher risk involved if bilateral, and barbell lifts are used.This study provides even more evidence in support of the specificity principle. The slow nature of the eccentric contractions do not directly relate to exercises that require a high rate of force development (as much force as possible in as little time as possible). Of course, when trained concurrently with rate of force developing exercises, it is possible that the strength gains from eccentrics may be beneficial.
Reference:
Wirth, K., Keiner, M., Szilvas, E., Hartmann, H., Sander, A., Wirth, P. D. K., & Landstraße, G. (2014). Effects of eccentric strength training on different maximal strength and speed-strength parameters of the lower extremity. The Journal of Strength & Conditioning Research. Ahead of Print.