Worth training unilaterally when injured?
According to numerous studies, no.
In fact, research has shown that correctly tailored exercise has not only been shown to strengthen the uninvolved side but maintain strength and sometimes even muscle mass in the injured limb!
Resistance training is a powerful stimulus for neuromuscular adaptation. These adaptations are not limited to the working muscle and have in fact been shown to result in increases in strength and neural drive in a contralateral, resting muscle.
The phenomenon resulting in this sparing’ of strength and size on an uninvolved limb is termed ‘cross-education.’ (1, 2) This has been demonstrated in numerous studies:
Andrushko and colleagues conducted a study on 16 participants whereby the nondominant forearm was immobilized in a cast, while participants were either assigned to an exercising group (eccentric wrist flexion, 3x/week) or a control group (no exercise) for 4 weeks. The study found that the resistance training group maintained not only strength, but also muscle cross sectional area of the wrist flexors in the immobilized limb.
Furthermore, Lepley and colleagues conducted a similar study, this time testing the effect of exercise on quadriceps strength and muscle activation in an uninvolved limb. The exercising group exercised their uninjured limb 3x/week for 8 weeks and the study again concluded that greater strength and activation occurred in the unexercised limb in the exercising group when compared to the control group. Similarly, a study conducted by Derakhti and colleagues tested the effect of unilateral training to either the left or right leg in 20 previously untrained individuals. The study was conducted over 10 weeks (34 sessions) of single-leg exercise completing both the leg press and leg extension.
Similarly, this study also concluded that the 10-week program resulted in a significant increase in both maximal strength and muscle size in the untrained leg, again demonstrating a cross-education effect.
Hence, the research demonstrates the benefits that training an uninjured limb can have on the injured limb. When you are injured, it’s important that you continue with a structured strength training program as your recovery outcomes are better.
Injuries can be a frustrating and demotivating time, especially if you let them keep you away from training. A tailored exercise routine during a time of injury can still benefit you!
At Inspire Fitness for Wellbeing we adopt this with many of our members in order to keep them on track to achieve their goals. We do this through our design of individually tailored exercise programs that can be shaped around a potential injury, in order to keep you active and improving your overall health and wellbeing.