Should You Exercise With Sore Muscles After a Workout?

If you are aching after a run or a session at the gym, you may be unsure whether to carry on exercising or allow your body time to recover.

This aching or stiffness that develops in muscles following exercise is called "delayed onset muscle soreness" (DOMS). It typically begins 12–24 hours after an exercise session and commonly reaches its worst point between 24 and 72 hours later.

In the majority of cases, DOMS resolves fully within three to five days. But how should you manage it while it lasts? Can you exercise when you are still sore? This is what the research indicates.

Why are muscles sore after a workout?

During exercise, very small tears – sometimes termed "microtears" – develop in muscle tissue. As the body sends fluid and nutrients to the affected area to repair it, inflammation occurs. This forms a normal part of recovery and contributes to gains in muscle size and strength.

However, inflammation also activates pain receptors, causing the soreness felt in the days following a workout.

The severity of soreness depends on the activity performed. DOMS is more common if you have not exercised for some time, try an unfamiliar form of exercise, or place a high load on your muscles – such as through weight training or running.

In essence, it is the muscles' reaction to an activity that is harder or more challenging than they are accustomed to.

The more regularly you repeat the same type of exercise, the less likely muscle soreness becomes.

Do you need to be sore after every workout?

Sore muscles are entirely normal, particularly when you are starting exercise. However, they are not automatically a useful measure of progress.

They simply show that your body is adjusting to a new form of activity or a sudden rise in training load.

They do not reveal whether the exercise has successfully built muscle or enhanced fitness – particularly when you have trained consistently while gradually raising your load or frequency.

For instance, a person who runs frequently is unlikely to become sore after one run, yet that session can still improve their fitness.

Likewise, if you regularly lift weights, moving to heavier weights than normal may produce only mild DOMS at most. Even so, every session can still support strength improvements and muscle growth.

Should you exercise while still sore with DOMS?

The answer depends on whether injury or performance is your main concern.

Training while you are recovering from DOMS will not cause harm. Yet some evidence indicates that soreness may reduce strength and performance. In practical terms, you are unlikely to lift as much weight or run as quickly when you have DOMS.

Research has also found that muscle damage can have a negative effect on balance. This could raise the chance of a fall or an injury, such as an ankle sprain.

One further study showed that soreness may impair skill performance – basketball shooting accuracy in this instance. You may therefore see an effect if you are exercising with particular performance targets in mind.

Are rest days necessary?

Including recovery days between exercise sessions appears to have little effect on long-term gains in strength or fitness.

Studies have compared training on successive days – for instance, Monday, Tuesday and Wednesday – with training on non-successive days – Monday, Wednesday and Friday.

They have found no apparent difference.

In one study, two groups completed the same full-body weight-training routine for seven weeks, either on three consecutive days or on three non-consecutive days. Both groups made similar gains in muscle strength and size.

In the same way, another study assessed two cycling groups following the same high-intensity interval training programme on either three consecutive or three non-consecutive days. At the end of three weeks, both groups had achieved identical overall improvements in aerobic fitness and time-trial performance.

These studies were relatively brief. It is therefore possible that, across a full training year, an occasional rest day could help sustain motivation and prevent injury.

Bottom line

Although you will probably feel stiffer or slower, exercising with sore muscles will not harm you and is unlikely to obstruct your training progress.

That said, it may be sensible to avoid activities dependent on balance – including intense jumping and landing movements – because the risk of injury may be slightly higher.

If your soreness is severe, there is limited evidence that massage or even an ice bath may aid recovery, though the benefit is small.

Although muscle soreness is normal, you should still pay attention to your body. Do not try to work through severe discomfort or pain, as it may indicate an injury.

Speak to a doctor if:

• your muscles are exceptionally sore and the soreness continues for more than seven days
• you have visible bruising around the sore muscle
• you experience sharp pain.

Hunter Bennett, Lecturer in Exercise Science, University of South Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.