Have you ever had a torn rotator cuff or broken arm and stayed home from the gym. Well don`t!
Research has shown that by performing single-side training with the non-injured limb it will minimize the effects of atrophy and accelerate healing in the injured arm. This effect is known as cross-education.You increase strength in the injured limb due to neural adaptations. You will still have to train bilaterally to trigger a hypertrophy response but you will not lose muscle as fast in the injured limb.
There is a study in the Journal of Exercise Science and Fitness that during the cross-education effect, there is a gain of strength in the range of 5 to 25 percent to the injured limb when training the opposite limb. Another major benefit is there will be less range of motion loss in the injured limb do to the cross-education effect.
Sariyildiz, M., Karacan, I., et al. Cross-Education of Muscle Strength: Cross-Training Effects are not Confined to Untrained Contralateral Homologous Muscle. Scandinavian Journal of Medicine and Science in Sport. April 2011. Published Ahead of Print.
Zhou, Shi. Cross-Education and Neuromuscular Adaptations During Early Stage of Strength Training. Journal of Exercise Science and Fitness. 2003. 1(1), 54-60.