09/10/2026
🔥 Feeling the burn during exercise? It’s not lactic acid!
For years, we’ve been told that the burning sensation in our muscles during intense exercise is caused by a build-up of “lactic acid”. But research tells a different story.
🧪 At the normal pH of our tissues, what we actually produce is lactate, not a build-up of lactic acid. Rather than simply being a waste product, lactate can also be used by the body as a source of energy.
So what causes that familiar burn? 🔥
During intense exercise, working muscles undergo several chemical changes. Specialised nerve endings detect a combination of these changes, contributing to the burning sensation we experience when exercising hard.
🤔 And what about soreness the next day?
That’s different again. The aching and stiffness that can appear 12–24 hours after unfamiliar or strenuous exercise is known as Delayed Onset Muscle Soreness (DOMS). It is associated with microscopic changes and the resulting inflammatory and repair processes within muscle tissue, particularly after exercise your body isn’t accustomed to. DOMS often feels most noticeable around 24–72 hours after exercise.
⚠️ Know when it may be more than normal exercise soreness.
A temporary muscular burn during challenging exercise and some soreness afterwards can be normal. However, symptoms that are more intense than the usual exercise burn, feel unusual, or continue beyond 48 hours without improving may warrant assessment for a possible injury.
Getting a problem checked can help you understand what’s going on before continuing to train and potentially making it worse.
👐 Our osteopaths assess musculoskeletal and sports-related problems and can advise you on appropriate treatment and return to activity.
📅 Book an appointment with us:
https://clientportal.uk.zandahealth.com/clientportal/cityosteopaths/home
📖 Read the full article from The Conversation:
https://theconversation.com/feeling-the-burn-its-not-lactic-acid-291432