Tap into your body’s natural cardio turbochargers

Lactic acid has always been seen as the enemy of your metabolism, limiting your success and leaving you sore the next day. Recent research shows that this is wrong: not only does lactate have nothing to do with “the burn”, it’s actually a secret source of fuel that can help anyone turbocharge their workout.“When athletes are training to push up their lactate threshold (LT), what they’re really doing is training their bodies to use lactate as fuel,” says Dr George Brooks, the study author and a lactate researcher at the University of California. By increasing your threshold, you can improve both the intensity of your training and your stamina. “Improving that threshold is crucial,” says Lance Armstrong. You heard the man. Here’s how.


Fast laps can sabotage form in the water, so you should aim to maintain efficiency at high intensities, says Terry Laughlin, founder of Total Immersion Swimming


Warm up for five minutes, then do this 500m test: start off at a pace you can hold for more than 500m, but build gradually so that your last 100 is at 90 percent effort. Count your strokes per pool length (SPL) in the first and last 100m.


Swim 100m repeats for 20 to 30 minutes, resting after each one for one-quarter of your swim time. Swim at your fastest pace that allows you to keep an SPL count one or two strokes below your count in the final 100m of your test.


“My philosophy was to push up LT by going just below it,” says Armstrong. Here’s how to follow his lead.


Using a heart-rate monitor, perform two five-kilometre time trials on flat roads, riding as fast as you can. Multiply the higher average heart rate by 0.92 and 0.95 to find the ideal range to boost your LT. So if your average heart rate was 185, your LT training range is 170 to 176.


LT intervals below six minutes have less training benefits, says training coach Jim Rutberg. Start with three six-minute stints, each followed by six minutes of active rest (relax, but keep moving). As you can, tack on 60- second blocks to each interval, eventually adding a fourth block. If you reach 10 minutes, retest.


A higher lactate threshold increases the pace you can sustain over short- to mid-range distances, powers you over hills and adds kick to your sprint.


Warm up, then run five kilometres at race pace. If you finish in 15 to 19 minutes, your threshold pace should be 25 to 30 seconds slower per kilometre than your five-kilometre pace; 20- to 24-minute finishes put your LT pace at 20 to 25 seconds slower; and 25 to 30 minutes – or if you’re a beginner – five to 10 seconds per kilometre slower.


Run four one-minute segments at LT training pace with 60 seconds’ rest, suggests running coach Jason Karp. Perform the five-kilometre test again after eight weeks.

START YOUR ENGINES…Your body draws its fuel, ATP, from three energy systems at any given time. Pictured: the contribution, by percentage of total output, for each system during an 800m race.Aerobic system This slow-burning fuel system is your primary supply during regular exercise. ATP comes from the breakdown of fats, blood glucose and glycogen, using oxygen as part of a chain reaction to clear waste.Anaerobic system This short-term, oxygen-free process fuels normal movement and sudden, intense bursts of strength. The boost from ATP and creatine phosphate, which are stored in the muscles, lasts only seven to 10 seconds.Anaerobic lactate system This high-intensity, oxygen-free process breaks down glucose. Lactate is formed from a by-product and can be used inside the mitochondria (the cells’ energy producers) as an additional fuel