For decades, when a trainee injured a limb, they avoided training the upper body or lower body (depending on whether the injury was an upper or lower body injury). A brand-new study published in the Scandinavian Journal of Medicine and Science in Sports provides even more support for an alternative approach: Train the healthy limb and the “injured” limb will receive the benefits.
Known as bilateral transfer or cross education, researchers had subjects immobilize one arm by wearing a cast for four weeks while training the immobilized arm. One group used standard repetitions; one group used negative only reps, in which a trainer lifted the weight and the trainee lowered the weight under control; a third group did no strength training with the healthy limb.
The results? Well, of course, the exercised limb improved in both muscle strength and size. More importantly, the immobilized limb maintained all previous muscle size and strength (and the negative only group performed even better than the standard rep group). In contrast, the control group who did not train the healthy arm lost 22% of their initial strength and 5% of their muscle size.