The misconception we used to have about lactate was that it was responsible for muscle fatigue and that this is what the burning sensation signified. Scientists knew our bodies produced more as we got tired and this meant that it got blamed for everything, from stopping muscle contractions to post-exercise muscle soreness.
In fact, lactate is an integral part of your body’s energy system. It’s produced during anaerobic exercise, when you use glycogen rather than oxygem for fuel, and helps to transport hydrogen ions – the cause of fatigue – away from your muscles.
Your body starts to produce lactate during moderate exercise, at a point called your lactate threshold, or LT1. For me this happens when my pulse is around 140bpm. At this point your liver can still clear lactate from your system with relative ease, meaning hydrogen ions are moved away from your muscles. During hard exercise – for me around 178bpm – you’ll hit LT2, or “onset of blood lactate accumulation”, where your liver can’t dispose of all the lactate your body is creating. So the hydrogen ions stay in your muscles and you feel a burning sensation.
Now that we understand this, your aim in training shouldn’t be to reduce the production of lactate but instead to get your body to use it effectively. It’s time to forget that idea of “my muscles are filling up with lactic acid, the finish line can’t come soon enough”.
Think fast
Tweaking your training can change the way your body manages lactate, helping to delay the onset of LT2 and the associated burn, but these tweaks will be slightly different depending on your sport.
For example, in football you have to recover from hard sprints while continuing to move around the pitch. To do this, focus on short, hard sprint efforts of 10 to 15 seconds that take you way beyond the point of LT2, separated by two or three minutes of ‘recovery’ where you’re still running at a hard pace, but just under LT2.
If you’re focusing on training for a marathon or another sport where you still have to work at a hard pace but aren’t putting in super-intense bursts of activity, you want to train closer to LT2. Do sprints at just above LT2, each one lasting two minutes, then do a minute’s recovery at just below LT2. You’ll only need to do these intervals five or six times per session to get some benefit.
Leading edge
Why should you care about lactate threshold training? Because working on it is going to pay off when you’re on the pitch or the track. You’ll be able to push harder for longer before your muscles start feeling tired, and that’ll give you a real edge over the opposition. Your recovery time will be reduced too, meaning that a burst of speed won’t leave you burnt out.
Improve your lactate threshold
First find your lactate threshold. Warm up, then strap on a heart rate monitor and go for a 30-minute run at the hardest pace you can. Record your heart rate for each of the run’s final 20 minutes. The average of that number is your LT2.
Training for long distance Run ten minutes at 105% of your LT2, then two minutes at 95%. Repeat four times.
Training for quick recovery Run at your LT2 for five minutes, then push up to 110% of your LT2 for one minute. Repeat three times.
