Here’s a line that every fitness enthusiast has heard at least once in their lifetime: ‘can you feel the burn?’
Now let me dish this out to you up straight — this one is not endorsed by any fitness sciences, rather by, as I like to call it —’bro-sciences’. The glorification of working out till you feel the ‘burn’ can also be attributed to fancy social media posts. The line sounds catchy, feels legit, and often motivational. I don’t blame people who fall for it. It’s convincing, also because it feels tangible — I worked out so hard that I felt my muscles burn! It must have been a good workout — which is what makes it almost psychologically undeniable as a good measure of workout.
Read the full post written by me for THE DNA that demystifies the myth, using pure science and facts
Let’s demystify this!
What causes the burn?
When your muscles undergo a strenuous activity beyond its aerobic threshold, a substance called lactate is produced. The body uses lactate or lactic acid to produce energy anaerobically (without oxygen). And this acid builds up in your body faster than it can be consumed for energy. The accumulation of this acid is what makes you feel a burning sensation.
How does the burn damage your body?
Exactly as it sounds, the burn, or rather the presence of lactic acid, is catabolic (muscle degenerative) in nature and literally ‘burns’ away your muscle tissue. Since it is a stress-induced production, it also compounds with the stress hormone called cortisol creating a catabolic, muscle loss-causing non-fat metabolising environment within the body.
Contrary to popular opinion, lactate build-up does not cause DOMS (delayed onset muscle soreness). It’s genuine muscle microtrauma that causes DOMS, which is a genuine measure of a good workout. When you feel soreness the next day or later, it’s a sign that your body is rebuilding itself as your muscles are developing. About 15 per cent of the lactic acid is reconverted to glucose by the body — which if not used, is converted to fat and stored. Something you don’t want if you are trying to lose fat.
Are there any benefits of the burn?
Studies have shown that the presence of lactic acid promotes mitochondrial biogenesis — which means that it induces muscle cells to produce more mitochondria. The mitochondria are the cells’ energy-producing factories. Which means that more mitochondria leads to faster and more efficient energy production in the long term.
To burn or not?
If you want to focus on building muscle and shedding fat, avoid the ‘burn’ — it is catabolic and fat retentive. If you want to build a fitter, stronger body, at least once a week, work out till you feel the ‘burn’ to improve lactate management and induce mitochondrial biogenesis. This is best done by the introduction of HIIT for cardio or reps to failure in weight training sessions once in 3-4 weeks.
But under no circumstances, for any individual, unless you are a lab rat for studies on lactic acid production, is it advisable to work out till you feel the lactic acid build-up causing a burn everytime you workout.