Athletes of any sport can benefit by using eccentric loading techniques in their traditional strength training programs. Eccentric training, which has been underused and undervalued, produces and improves factors that affect strength, power, running economy, and injury prevention.
Eccentric contractions occur when muscles extend, or lengthen, while producing force. This muscle action yields greater force levels, up to 20-60% greater than concentric motions, with subsequent heightened neuromuscular activation levels (Mike, Kerksick, and Kravitz, 2015).
Higher strength activity relates to muscle elasticity and the stretch-shortening cycle that occurs with eccentric contractions (Wirth, Keiner, Szilvas, Hartman, and Sander, 2015). Muscles contract eccentrically during deceleration activities such as downhill running, jump landings, and other forms of impact absorption while strength training (Maciejczyk, Wiecek, Szymura, Ochalek, Szygula, Kepinska, and Pokrywka, 2015).
Eccentric exercises done with supramaximal loads primarily induces neural adaptation while submaximal loading elicits hypertrophic effects. The use of one over the other depends on the individual athlete’s needs (Wirth et al., 2015).Eccentric loading causes adaptation in both concentric-only and eccentric-only strength movements. Click To Tweet
Interestingly, eccentric loading allows for positive adaptation in both concentric-only and eccentric-only strength movements (Mike et al., 2015). Eccentric exercise improves various aspects of athletic development, including anaerobic power, acceleration, endurance, and maximum strength. Examining these parameters through literature helps us to understand how eccentric resistance training can directly affect each variable.
One study found that three weeks of eccentric training combined with overspeed training enhanced power and running speed in trained athletes (Cook, Beaven, and Kilduff, 2013). Eccentric exercises improved aspects of muscular power while overspeed training directly influenced velocity.
In the Cook study, the following training groups were compared for performance outcomes on speed and power: traditional resistance training, eccentric-only activity, traditional resistance training plus overspeed training, and eccentric-only plus overspeed training. The researchers tested twenty semiprofessional rugby players for changes in strength, power, and speed after they consecutively performed four counterbalanced three-week training blocks.
The traditional program called for two lower body and two upper body sessions per week. The eccentric-only program was set up in the same manner except the players only performed the eccentric movement, and spotters returned the weight to the rack between every repetition. Band-assisted sprints and vertical jumps were used for overspeed training.
The researchers discovered that eccentric-only training elicited greater hypertrophy and strength effects for both upper and lower body training. Adding overspeed training, which accentuates the eccentric loading on the lower body, elicited the greatest performance enhancements, specifically peak power in the countermovement jump.
No change in maximal speed was observed from the eccentric-only group. When combined with overspeed training, however, the players did produce gains in speed. For practical application, the researchers recommended focusing on both force adaptation and movement velocity to produce the best possible training outcomes.
A separate study by Wirth et al. (2015) examined the effects of eccentric training on lower body maximal strength and speed-strength (power) in untrained subjects. The training group performed three lower body strength sessions each week for six weeks using a 45-degree unilateral leg press. This group was compared to a control group which did not do the training.
Eccentric maximum strength, traditional eccentric-to-concentric 1-rep maximum, maximum voluntary contraction, and vertical jump performance were evaluated at both the beginning and end of the training period. At the end of the six weeks, eccentric strength improved by 28.2% and absolute strength by 31.1%. No significant change was seen in the speed-strength motor components of the vertical jump and force contraction tests.
The Wirth study supports the Cook study in that eccentric training alone elicited strength gains, but supplemental training may be required to target specific power adaptations.
In cycling, athletes with greater lower body lean muscle mass tend to have a ~4-9% increase in mean power maximum per kilogram of lean mass (Mujika, Ronnestad, and Martin, 2016). The main concern with incorporating strength training, specifically heavy sets, is the fear of adding unnecessary bulk to the muscles which would hinder performance.
The research shows, however, that heavy weight eccentric training paired with relatively high-volume endurance training makes the bulking adaptation physiologically impossible (Mujika et al., 2016). While some studies have found a slight increase in muscle hypertrophy (2-4%), there was no increase in total body mass in trained cyclists (Mujika et al., 2016).
Since cycling is a concentrically-dominant sport, why incorporate eccentric activity at all? Because one form of endurance training that specifically targets the eccentric component of a cyclist’s movement pattern involves inverse dynamics (focus on the ‘pull’ component). This allows the knee and hip joints to absorb most of the cycling power through each rotation (Mujika et al., 2015).
This type of training is gaining much attention not only for its positive effects on power development but also its effects on rehabilitation and injury prevention (Mujika et al., 2015). Sport-specific training focuses exclusively on maximal concentric movements, but overuse studies remind us how important it is to train the opposable, antagonistic movements for well-rounded strength adaptations and decreased likelihood of injury.
The question remains–how do we safely incorporate this type of training into an athlete’s program? Program design is important to any athlete’s performance success from a long-term perspective. Educated strength and conditioning professionals decide how and when to incorporate this type of activity.
In a study by Maciejczyk et al. (2015), healthy, active individuals participated in a 60-minute downhill running test at a -10% grade as well as a 20-second maximum cycling sprint test. The researchers studied the effect on anaerobic power, starting speed, and anaerobic endurance.
Eccentric exercise caused a significant decrease in peak power for at least twenty-four hours after the test but had no effect on starting speed or anaerobic endurance. This power decrease should be taken into account when planning sessions that require quality power output.
A recent paper by Mike et al. (2015) described methods to include eccentric training in a resistance program. Eccentric movements are performed in a slow and controlled manner, typically lasting 3-5 seconds when the eccentric component is emphasized or even up to 8-10 seconds for exclusively eccentric movements. The sets and reps will depend on the desired outcome. Typically 3-5 sets of each exercise are performed with 6-8 reps for a strength focus or 8-10 reps for a hypertrophic/power focus. Higher velocity options are also available but are only appropriate for advanced athletes.
The authors offered several ways to perform eccentrics as part of a resistance training program. The 2/1 technique involves lifting the weight with two limbs through the concentric phase and using only one limb for the eccentric phase. The typical load is 70% of the concentric 1-rep maximum.
For a super slow technique, a 60% maximum load typically is lifted through the eccentric phase for 10-12 seconds. Another technique suitable for advanced athletes is the two-movement technique where 90-110% of maximal load is lifted through a compound, multi-joint movement and ended with an isolation exercise for the eccentric finish. For example, performing a concentric dumbbell bench into an eccentric dumbbell fly.
The negative, or supermax, technique requires at least one spotter for correct execution. In this lift, the athlete does not perform the concentric movement. Instead, a supramaximal weight 110-130% of maximum is lifted eccentrically through one repetition for 3-10 sets with spotters resetting the weight between each repetition.
Cook, Christian J., Martyn C. Beaven, and Liam P. Kilduff. “Three Weeks of Eccentric Training Combined with Overspeed Exercises Enhanced Power and Running Speed Performance Gains in Trained Athletes.” Journal of Strength and Conditioning Research 27(5) (2013): 1280-1286. doi: 10.1519/JSC.0b013e3182679278.
Maciejczyk, M, M. Wiecek, J. Szymura, K. Ochalek, Z. Szygula, M. Kepinska, and A. Pokrywka. “Effects of Eccentric Exercise on Anaerobic Power, Starting Speed, and Anaerobic Endurance.” Kinesiology 47(1) (2015): 44-50.
Mike, Jonathan, Chad M.Kerksick, and Len Kravitz. “How to Incorporate Eccentric Training Into a Resistance Training Program.” Strength and Conditioning Journal 37(1) (2015): 5-17. doi: 10.1519/SSC.0000000000000114.
Mujika, Innigo, Bent R. Ronnestad, and David T. Martin. “Effects of Increased Muscle Strength and Muscle Mass on Endurance-Cycling Performance.” International Journal of Sports Physiology & Performance 11(3) (2016): 283-289. doi: 10.1123/IJSPP.2015-0405.
Wirth, Klaus, Michael Keiner, Elena Szilvas, Hagen Hartmann, and Andre Sander. “Effects of Eccentric Strength Training on Different Maximal Strength and Speed-Strength Parameters of the Lower Extremity. Journal of Strength and Conditioning Research 29(7) (2015): 1837-1845. doi: 0.1519/JSC.0000000000000528.