What are the causes of muscle pain after exercise?

Mark
Written By Mark

Have you ever gone to the gym, lifted weights, and then had severe muscle pain the next day? What’s the reason? What is the treatment?

Who hasn’t suffered from muscle pain at some point? The truth is that this physical pain that usually appears days after exercising is nothing more than a defense mechanism for our body.

It is also known as delayed onset muscle pain (DOMS). José Santos, Secretary General of the Professional College of Physiotherapists of the Community of Madrid, explains in statements to the Spanish website CuídatePlus that this painful syndrome is “characterized by a loss of strength.” Muscles (up to 10-12%), after performing high-intensity eccentric exercises, and in very specific muscles, responsible above all for propulsion, such as the leg muscles or the quadriceps.”

Santos also points out, “If we could observe the muscle with a microscope, we would see tiny lesions at the level of the connective tissue sheaths of the muscle that release substances that stimulate pain receptors.”

Muscle pain caused by muscle soreness usually lasts 5 to 7 days – with peak intensity appearing 1-3 days after exercise – which is why we feel muscle pain more than on the second day of exercise.

Why do muscle pain occur?

Delayed muscle pain affects both experienced and novice athletes, and the severity of the pain is greater the more intense the exercise is performed.

As for the causes of muscle pain, there is not just one factor, but rather many factors that affect its appearance.

The following are theories that may explain muscle pain after exercise:

  • Mechanical theory: This is the most widely accepted theory at present and is based on the observation of microscopic lesions (micro-tears) in muscles after exercise. The areas most affected by this pain are the muscle joints and tendons near the joints.
  • Thermal theory: The high temperature inside the muscle causes cell death, and this can lead to a structural defect in the muscle, which stimulates the nerve endings that cause the sensation of pain. This theory is complementary to the micro-rupture of muscle fibers, as it can be considered another reason for this.
  • Inflammation theory: Once a muscle is exposed to trauma, the accumulation of some metabolic substances (especially bradykinin, serotonin, histamine, and potassium) is responsible for the inflammation accompanying any injury to the muscle fibers, and when the accumulation reaches a certain level, the nerve endings that transmit the sensation of pain are activated. “Since it takes time for all these substances to accumulate in the damaged muscle cells,” this explains why muscle pain is not felt until 24 hours later.
  • Metabolic theory: This theory explains that “under conditions of hypoxia, such as during intense exercise, the metabolism produces less energy than the oxygen-rich metabolism, and glucose also turns into lactic acid, which is deposited in the muscles.” The pain will be a result of increased acidity (which is picked up by the nerves) and micro tears in the muscles due to the crystals.

Can muscle pain be avoided?

Some experts say that muscle pain is part of the adaptation process to training and should not be prevented.

But there are some tips that will help us reduce this annoying sensation:

  • Warm up.
  • Exercise regularly.
  • Start with a moderate level of activity and gradually increase exercise intensity. You should never overdo physical exercise. Everyone has their own limits and everyone should know how far they can go.
  • Hydration, by drinking fluids, such as water, milk, and sugar-free tea.
  • Stretching exercises at the end of the session, which is as important as the warm-up. It has been proven that stretching does not prevent muscle pain, but it relieves it.
  • Massage: Although there is no clear scientific basis for this, superficial massage can help reduce muscle pain in some athletes.