Fixing Muscular Imbalances

Muscular imbalances are very common amongst athletes and every-day gym goers. Most common and most noticeable imbalances are bilateral. Bilateral is defined as concerning both sides of the body or body part (Oxford Dictionary of Sports Science and Medicine, 2012) . This is portrayed most commonly as differences or imbalances between limbs. Schlumberger et al., (2006) refer to this as bilateral muscular imbalance.

Bilateral muscular imbalance may occur for a number of reasons. It can be the result of previous injury, sporting demands or even side preference (Nadler et al., 2001, Rahnama et al., 2005).

This muscular imbalance has been shown on multiple occasions to be associated with an increased risk in injury (Hewett et al., 1996, Knapik et al., 1991, Myer et al., 2004, Orchard et al., 1997) and lower back pain (Nadler et al., 2001).

Bampouras & Dehurst (2018) indicate that bilateral muscular imbalances can impact both biomechanics and strength of the lower limbs, which subsequently affects sporting performance (Flanagan & Harrison, 2007, Impellizzeri et al., 2007, Jordan et al., 2015, Young et al., 2002). An example of this can be taken from the study carried out by Young et al., (2002) where it was reported that athletes turned faster in change-of-direction tests when they were pushing off their dominant leg, with this dominance affecting overall performance. If you think of this in relation to tennis performance, it could be the difference between winning and losing a point, game, set or match.

Strength has been shown to reduce the risk of injury (Malone et al., 2019) so it is no surprise that an increased risk of injury comes with bilateral muscular imbalances. When you couple this with the evident biomechanical differences (reference) it is clear that muscular imbalances are cause for concern and should be addressed.

Practical Applications

It is common that in bilateral exercises such as the bench press, military press, deadlift, squat that are loaded using a barbell, for individuals with muscle imbalances, the stronger or more dominant side will contribute slightly more than 50% of the workload, and therefore overcompensate for the weaker side. Unilateral exercises are the most obvious way to close the gap and reduce the imbalances, however sometimes even loading with dumbbells can do the trick.

For the lower body there are lots of barbell, dumbbell and body weight variants of the same unilateral exercises that can be utilized to address these imbalances. For example, body weight, dumbbell and barbell split squats and Bulgarian split squats can be used. The same can be said for lunges, reverse lunges and Romanian deadlifts. Single leg squats are more difficult to load but are also a great option for addressing bilateral lower limb muscular imbalances.

When it comes to the upper body, exercises are a little more limited. However, just replacing a barbell for dumbbells will force both sides of the body to work equally hard and can be very effective at addressing weakness and imbalance. Another option here is alternating exercises such as alternate dumbbell bench press, shoulder press or single arm rowing variants.

With all of the above, it is important that the load is dictated by the capabilities of the weakest side or muscle group. This way the gap will begin to close, and the imbalance will be addressed.

For example, it is no use loading the stronger side of the body so that it is challenged, but not be able to match this on the weaker side. This will continue to increase the gap and result in greater muscle imbalances.

It is advised to begin each set with the weakest side of the body, at a load that is challenging, and to match this on the stronger side of the body.

In doing so, the imbalance and weakness will reduce and result in improved sporting performance and reduced risk of injury.

Train smart,

Joe