Lactic Acid: What It Is and Why It’s Not the Villain in Exercise

If you’ve ever pushed yourself in the gym, on the sports field, or during a fitness challenge, you’ve probably felt that familiar “burn” in your muscles. For years, lactic acid was blamed as the culprit behind muscle pain, fatigue, and even next-day soreness. But science now shows the story is much more interesting—and much more encouraging for anyone who wants to stay active.

At SSCP, we want to clear up the confusion and help you understand how your body really works during exercise.

What Is Lactic Acid?

When you exercise, your muscles need energy. The body usually creates this energy by using oxygen to break down glucose (sugar). But when you’re working at high intensity—like sprinting, lifting heavy, or pushing to your limits—your muscles can’t get oxygen fast enough.

That’s when your body switches gears and produces energy without oxygen (anaerobic metabolism). A by-product of this process is lactate (commonly called lactic acid).

Myth Busting: Lactic Acid and Muscle Pain

For decades, lactic acid was blamed for post-exercise soreness. But here’s the truth:

• Lactate doesn’t cause delayed onset muscle soreness (DOMS). That stiffness and soreness you feel the next day is actually due to tiny micro-tears in your muscle fibres, which is part of the natural strengthening process.

• Lactate is actually fuel. Your body can recycle and reuse lactate as an energy source once oxygen becomes available again. In fact, well-trained athletes are often very efficient at “clearing” lactate and using it to keep performing.

Why Do Muscles Burn Then?

The burning sensation during hard exercise isn’t from lactic acid itself, but rather from the accumulation of hydrogen ions that change the acidity (pH) in your muscles. This creates that temporary “burn” feeling. Once you slow down or stop, your body quickly balances things out.

The Role of Physiotherapy

Understanding lactic acid is important, but here’s where physiotherapy comes in:

• Performance guidance: We can help you train smarter by tailoring your exercise intensity and recovery strategies.

• Recovery techniques: Tools like active recovery, stretching, and targeted treatments can assist your body in clearing lactate and reducing fatigue.

• Injury prevention: By improving your biomechanics and conditioning, we help you avoid pushing past your body’s safe limits.

Key Takeaways

• Lactic acid isn’t your enemy—it’s actually a helpful part of your body’s energy system.

• Muscle soreness after exercise is caused by tissue micro-damage, not lactate.

• Physiotherapy can help you recover better, train smarter, and stay injury-free.

So, next time you feel the burn during a workout, know that your body is simply working hard and efficiently. And if you’d like professional support to optimise performance or speed up recovery, our team at SSCP is here to help.