Post-workout soreness, commonly known as Delayed Onset Muscle Soreness (DOMS for short), is a familiar sensation for most. For some, the ache is a satisfying feeling; you know you’ve challenged yourself and are growing stronger. For others, it can be an uncomfortable nuisance. Whether you like the feeling or not, DOMS can leave you pondering whether it’s acceptable to push through the discomfort and exercise or if it’s better to let your body rest. 

Well, we have to give you the same (somewhat annoying) answer that applies to most questions in the realm of fitness: that depends! There are many factors to consider when deciding whether or not to train on sore muscles, and as mobile and virtual personal trainers, we examine each case individually. 

Here are a few things to consider next time you’re deciding whether or not to take a rest day due to sore muscles:

Deciding to take a rest day

UNDERSTANDING DOMS

Delayed Onset Muscle Soreness (DOMS) is common after engaging in physical activities that involve unfamiliar or intense exercise. It typically manifests as muscle discomfort, stiffness, and tenderness, peaking 24 to 72 hours after a workout. However, in some cases, DOMS can occur just a few hours after activity. 

Contrary to popular belief, DOMS is not solely caused by lactic acid – a bodily compound produced in your muscles (and other bodily tissues) during intense physical activity or when there is an insufficient supply of oxygen to meet energy demands. Rather, DOMS is likely the result of microscopic damage to muscle fibres during muscle-lengthening (eccentric) contractions and forceful, unfamiliar exercises. This muscle damage triggers an inflammatory response, which contributes to the soreness and stiffness of DOMS. 

As the body repairs and adapts to exercise-induced stress, muscles become stronger and more resilient. This is how we build strength over time. That said, muscle soreness in general is still “an active area of research and one that will hopefully lead to new and more effective treatments for not only those experiencing minor muscle soreness, but also those living with chronic muscular pain” (Forbes Health, 2023). While post-exercise DOMS can be uncomfortable, for most, it’s a natural part of the adaptation process that accompanies physical training and fitness. 

FACTORS TO CONSIDER

The first thing to consider when deciding whether or not to train on sore muscles is the intensity of your soreness. Mild soreness may indicate your muscles are adapting to new challenges and could benefit from light exercise. Severe soreness may suggest your muscles need more time to repair, and exercising could exacerbate the damage. Remember: strength is built at rest, so training too soon can diminish or prevent results. 

Secondly, you need to think about the type of exercise you’re doing. Low-impact activities like walking or swimming may be gentler on sore muscles compared to high-impact or heavy resistance training. A great tactic is to alternate exercise forms and/or movements to engage different muscle groups. This allows appropriate recovery in the affected areas while keeping your level of activity high. 

Another area of importance is personal tolerance. Everyone’s pain threshold varies, and what might be manageable soreness for one person may be debilitating for another. Pay attention to your body’s signals and avoid pushing yourself to the point of pain.

Lastly, think about your overall health and fitness level. A well-conditioned individual may find light exercise on sore muscles beneficial for improving blood flow and reducing stiffness. Beginners or those returning to exercise after a hiatus may require more recovery time.