Muscle pain: causes and ways to relieve it

Author: Frédéric Delavier and Michel Gundill: chapter from the book "Nutritional Supplements for Athletes".
2011-09-05

Muscle pain is the main problem faced by beginners or athletes who have resumed training after a long break. Fortunately, in most cases, it is temporary and short-term.

It is a misconception that muscle pain occurs because the muscles are saturated with lactic acid. In the worst-case scenario, it takes about one hour to clear lactic acid from the body after extreme physical exertion, but usually, traces of lactic acid disappear from the muscles and blood within 20 minutes. Muscle pain typically appears 24-48 hours after physical activity. Moreover, the pain caused by lactic acid feels like a strong burning sensation and is nothing like the soreness from physical exertion.

Researchers have established that muscle pain arises from micro-traumas in muscle fibers. Indeed, the pain that arises is often provoked by numerous micro-injuries to the muscles. But why does it appear so long after the physical activity has ended? Some micro-injuries occur not during, but after the workouts. Repeated contractions and unfamiliar stretching of the muscles cause calcium to flow out of the cells. This calcium regulates muscle contractions. However, once it has fulfilled its purpose, calcium creates its own separate reserves. The integrity of these "stores" is disrupted when the muscles start working intensively. This release occurs slowly and culminates just before muscle pain appears, which explains why we begin to feel pain in the muscles a few hours after exercising.

Protective Action of Proteins

In a study conducted by P. Fleckollm among those receiving protein supplementation immediately after workouts, it was found that problems related to muscle pain decreased by 26%. This indicates better muscle adaptation, which is associated with protein consumption at the very early stage.

K. Van Someren (2005) recorded a reduction in pain with regular daily intake of three grams of 3-hydroxy-methylbutyrate and three grams of ketoisocaproic acid in untrained men over two weeks. This combination prevented a twofold increase in catabolic indicators, which was noted in those who were given a placebo after workouts that led to injuries.

In young men and women taking five grams of BCAAs, soreness and muscle fatigue decreased within four days after training (Y. Shimomura, 2006).

In a study conducted by M. Millard-Stafford (2005), runners first completed a 21-kilometer distance and then a shorter distance for speed. After that, they were given a two-hour rest before undergoing similar tests again. During the rest, one group received a drink containing six percent carbohydrates, the second group received the same drink with ten percent carbohydrates, and the third group received a combination of carbohydrates (eight percent) and whey protein (two percent). The results from the second phase were similar across all three groups. However, the combination of carbohydrates and protein helped reduce the sensation of muscle pain by half compared to consuming carbohydrates alone.

Conclusions:

Timely consumption of a protein or carbohydrate-protein mixture (immediately after training) can significantly reduce muscle pain. This is likely related to the prevention of micro-traumas in muscle tissues that occur after workouts, as well as to inhibiting muscle catabolism.