Increase tendon strength and prevent injury by doing eccentric training. Manipulating the eccentric phase of a muscle action will keep you healthy and provide numerous performance benefits, while injecting variety into your training to keep you from getting bored.
A new review in the Strength and Conditioning Journal reminds us of the value of programming eccentrics for athletes and the recreational population. Eccentric training is probably best known for producing strength gains and increasing power and jump height. But, did you know it can also help you strengthen tendons, increase flexibility, and prevent injury?
Extensive research shows that eccentric training can increase tendon strength because it promotes collagen production. Remember that tendons have a slow metabolic rate with limited blood supply, making them very slow to heal. Eccentric movements will stimulate blood flow, promote tendon healing, and activate mechanoreceptors in the cells of the tendon, increasing tendon strength.
Eccentrics will also lengthen the muscle-tendon unit, increasing range of motion (ROM) or flexibility around a joint. For example, eccentric training is commonly used to rehabilitate, strengthen, and lengthen the Achilles tendon..
Authors suggest a minimum of 12 weeks of eccentric training for tendon remodeling and regeneration. Three sets of 15 reps, with increasing repetitions are typically used in the literature, but a better method is to progressively increase load and decrease reps as an individual progresses to restore tendon strength and joint function.
A second new analysis in the British Journal of Sports Medicine showed that eccentric training will produce clinically significant increases in flexibility in the ankle and hip joints. For example, at the hamstring, a 6-week eccentric program increased joint ROM increased by as much as 13 degrees. A 14-week eccentric training program increased hip ROM by an average of 22 percent.
Researchers suggest eccentric training increased the sarcomeres in series within the muscle, which increases the joint angle at which peak torque is generated. Better joint range of motion and ability to produce peak muscle tension at the optimum muscle length have been shown to lead to a lower injury risk in athletes. Plus, flexibility is often an impediment to proper technique in the deep squat, deadlift, power clean, and front squat, and eccentric training can help solve this as well.
Good news is that studies suggest the value of eccentric training can be seen in practice by keeping athletes healthier on the field. Two studies of elite soccer players showed that eccentric hamstring training dramatically decreased injury rates in the hamstrings.
There is no downside to including eccentric training in your program (besides soreness afterwards) since it will help you increase flexibility, while boosting tendon and muscle strength. If you are new to eccentric training, begin by manipulating tempo with a 4-second eccentric phase and a 1-second concentric phase. This can be varied to use a longer eccentric phase and an explosive concentric motion.
O’Sullivan, K., McAuliffe, S., et al. The Effects of Eccentric Training on Lower Limb Flexibility: A Review. British Journal of Sports Medicine. 2012. Published Ahead of Print.
Petersen, J., Thorborg, K., et al.. Preventive Effect of Eccentric Training on Acute Hamstring Injuries in Men’s soccer. American Journal of Sports Medicine. 2011. 39(11), 2296-2303.
Schache, A. Eccentric Hamstring Muscle Training Can Prevent Hamstring Injuries in Soccer Players. Journal of Physiotherapy. 2012. 58(1), 58.
Cowell, J., Cronin, J., et al. Eccentric Muscle Actions and How the Strength and Conditioning Specialist Might Use Them for a Variety of Purposes. Strength and Conditioning Journal. 2012. 34(3), 33-48.