As a competitive athlete, ‘no pain, no gain’ is no less a way of life as it is a motto. If I didn’t feel the burn after working out, then I’d feel like I didn’t exercise hard enough. It made sense to me: in order to gain muscle, you have to work your muscles repeatedly and with increasing weight in order for them to grow and develop.

I ended up learning the hard way that pain and muscle soreness are not always the same. What might seem like an indication of a successful workout could actually be the start of an injury. But at what point does pain no longer equate to the gains we actually want? And why is the idea of ‘no pain, no gain’ an unhealthy one?

Let’s start with the physiological basics.The human body is composed of hundreds of skeletal muscles, which are composed of myofibrils and sarcomeres that form muscle fibres. These fibres are responsible for all basic movements and contractions. The skeletal muscles contract when they receive signals from motor neurons in the brain. The easier it is for the skeletal muscles to receive those signals, the better the body becomes at contracting the muscles, which leads to more strength gains.

After a workout, the body repairs and replaces all damaged skeletal muscle fibres by amalgamating them to form new, thicker myofibrils. Every time the body needs to repair and replace the damaged fibres, they increase in thickness and number, which equates to muscle growth. If the body is creating new microfibrils quicker than they are breaking down, there is more muscle growth.

This is how the idea of ‘no pain, no gain’ came about: you essentially need to be working out more, thus experiencing more pain, in order to gain more muscle. What many don’t realize is that general pain and muscle pain are not always the same; to understand the differences, you need to understand what muscle soreness actually is.

The medical term for muscle soreness is Delayed Onset Muscle Soreness (DOMS). According to the American College of Sports Medicine, any activity or motion that the muscles aren’t accustomed to could lead to DOMS because motor neurons rarely, if ever, send those specific signals to muscle fibres instructing them to contract in those ways.

Most people believe that the origins of DOMS is a result of microscopic damages done to the muscle fibres involved in the motions of certain novel exercises.

Everyone is susceptible to DOMS — even professional athletes — especially when doing novel exercises or motions. However, the severity of DOMS can differ from person to person depending on how they have adapted to the novel exercises, the speed at which they perform the exercise, and how long they perform it. Just one bout of DOMS can end up having a partial protective effect on muscle fibres that will reduce the severity or even likelihood of experiencing DOMS the next time the body partakes in a specific exercise.

There is one aspect of DOMS that greatly contributes to why ‘no pain, no gain’ is only a myth: its longevity. The effects of DOMS don’t just last a couple of days — decreased range of motion and a reduction in muscle strength may last for as long as 10 days after the initial exercise.

That means individuals who do the same exercises, or more challenging ones, without taking time for rest and rehabilitation, run the risk of a more serious injury like a muscle strain or tear. These normally occur when the muscle has been overstretched or torn because of fatigue, improper use, or overuse. According to a study by scientists at John Hopkins University, the cause of muscle strains is not even restricted to rigorous exercises; they can result from walking. Individuals can even develop chronic muscle strains from doing repetitive movements daily.

So why do many athletes still swear by the notion of ‘no pain, no gain?’ Researchers believe it’s due to athletes’ high pain tolerance. Since they regularly put their bodies through rigorous and repetitive exercise routines, they’ve been unconsciously forced to adapt and be more relaxed in their attitudes toward pain.

Athletes employ the cognitive strategies of association and dissociation to strengthen their pain tolerance levels and achieve maximum performance. If athletes remind themselves that the pain they are experiencing is being induced by an activity or motion that they could reduce or even stop at any time, it can apparently relieve much of that pain.

Many experiments dealing with pain tolerance have shown that when athletes use this strategy, they can withstand pain for significantly longer periods of time. It is important to add that there is still much research that needs to be done on the physiological mechanisms and reasoning behind why these strategies work.

Other researchers believe that the idea of pain equalling gain stems from the way people tend to approach exercise in general. Dr. Jeffrey Berg, an orthopaedic sports medicine doctor who formally served as an orthopaedic surgeon and physician for the NFL team Washington Redskins, has devoted much of his research to this idea. He has found that the majority of people don’t ease into exercise as slowly as they should. Putting your muscles through vigorous exercises requires patience and a thorough understanding of your body’s limits. Berg believes that individuals confuse more serious joint, bone, and tendon strains and pains with the less serious DOMS. In actuality, these two types of pain are drastically different: the former is far more dangerous and can lead to lifelong injuries.

The take-home lesson is that before exercising, you should get to know your body. Understand your pain tolerance and limits, and if you’re planning on taking up a sport or serious exercise regime, be sure to get rest and be aware of sports injury rehabilitation. Not all pain will lead to beneficial gains, so prioritize your own health and safety.

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