Should You Exercise With Sore Muscles After a Workout?

If you feel achy after a run or a gym workout, you may be unsure whether to carry on training or allow your body time to recover.

The aching or stiffness that develops in your muscles following exercise is called "delayed onset muscle soreness" (DOMS). It generally begins 12–24 hours after a workout and commonly reaches its worst point between 24 and 72 hours afterwards.

In most cases, DOMS resolves entirely within three to five days. So what should you do until then? Can you exercise while you are still sore? Here is what the evidence indicates.

Why muscles become sore after a workout

During exercise, small tears - known as "microtears" - develop in your muscles. Your body then sends fluids and nutrients to the affected area to repair the damage, triggering inflammation. This is a normal element of recovery and helps promote gains in muscle size and strength.

However, inflammation also activates pain receptors, causing the soreness you experience in the days following your workout.

The level of soreness you experience depends on the activity you have done. DOMS is more common if you have not exercised for some time, try a new kind of activity, or place substantial demands on your muscles - for instance, through weight training or running.

In essence, it is your muscles reacting to an activity that is more difficult or demanding than they are used to.

The more regularly you perform the same form of exercise, the less likely you are to become sore.

Do you need sore muscles after every workout?

Muscle soreness is entirely normal, particularly when you are starting out with exercise. However, it is not always a reliable sign that you are making progress.

It simply shows that your body is adjusting to a new type of exercise or a sudden rise in training load.

It does not show whether that exercise has successfully improved fitness or built muscle - especially when you have trained consistently while gradually increasing either your load or frequency.

For instance, a person who runs often will probably not become sore after one run, although that session will still improve their fitness.

In the same way, someone who lifts weights regularly may experience only mild DOMS when using weights that are heavier than usual. Nevertheless, every session will still contribute to greater strength and muscle growth.

Should I exercise while I still have DOMS?

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

Training as you recover from DOMS will not cause harm. Yet some evidence indicates that soreness may reduce strength and performance. As a result, you are unlikely to be able to lift as heavily 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 a sprained ankle.

A further study showed that soreness may reduce skill performance - basketball shooting accuracy in that case. Therefore, you may notice an effect if you are exercising with particular performance objectives.

Do rest days affect strength and fitness?

Having recovery days between workouts does not appear to make a great deal of difference to long-term improvements in strength or fitness.

Studies have compared training on consecutive days - such as Monday, Tuesday and Wednesday - with training on non-consecutive days, such as Monday, Wednesday and Friday.

They do not appear to show a difference.

For example, one study asked two groups to complete the same full-body weight-training programme over seven weeks, either on three consecutive days or on three non-consecutive days. Both groups achieved similar gains in muscle size and strength.

Likewise, another study compared two groups of cyclists following the same high-intensity interval training programme on either three consecutive or three non-consecutive days. After three weeks, the groups had made the same overall gains in aerobic fitness and time-trial performance.

These studies were relatively short. It is therefore also possible that, across a full year of training, including an occasional rest day may help sustain motivation and prevent injury.

The bottom line on exercising with sore muscles

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

That said, you may wish to avoid activities requiring balance - including intense jumping and landing movements - because your injury risk may be slightly higher.

If you are very sore, some evidence suggests that massage or even an ice bath could aid recovery, although the benefit is small.

Although muscle soreness is normal, you should still pay attention to your body. Never train through severe discomfort or pain, as it may indicate an injury.

Speak to a doctor if:

• your muscles are extremely sore and the soreness continues for more than seven days
• you have visible bruising on 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 licence. Read the original article.