...I GAS OUT?
Physiology might not be on your mind as you gasp for air on the gym floor. But a little knowledge goes a long way – and will ensure you last the course
01 FILL YOUR TANK
If going full-send leaves you in a quivering heap, check your diet. When your body is asked to perform repeated, forceful muscular contractions, it taps into stored carbs for fuel: ‘They’re used at a fast rate during high-intensity efforts, so make sure you don’t go in depleted,’ says exercise physiologist Tom Cowan. Dehydration also impairs the delivery of oxygen to your muscles, while increasing heart rate and strain on the body. And box jumps are hard enough.
02 HEAL THE BURN
‘At high intensities, when oxygen demand from the working muscles exceeds supply, those muscles rely on anaerobic pathways to produce energy,’ says Cowan. Carbs are broken down to produce lactate, and hydrogen ions start to accumulate, leading to The Burn. Training raises your anaerobic threshold, so you can go harder before that pain sets in. Use your rest time wisely, too: ‘Active recovery such as walking between sets clears blood lactate quicker than passive recovery (rest).’
03 DEEP BREATH NOW...
It’s not just your quads that are working hard – so are your respiratory muscles, as your breathing quickens along with your heart rate. ‘Perform a warm-up for five to 15 minutes before your workout,’ says Cowan. Elevating your heart and breathing rates before the countdown timer beeps ensures your muscles have a better oxygen supply. Serious about improving your breathing muscles? Consider buying an inspiratory muscle training (IMT) device.
04 JOIN THE ‘A’ TEAM
‘Explosive movements such as jumps or sprints recruit fast-twitch (type II) muscle fibres,’ says Cowan. These fibres fatigue quickly – but they can adapt. Hardcore type IIA fibres don’t tire as fast as type IIX, making them better for workouts that mix power and endurance. Regular heavy resistance training will transform more of your IIX fibres to extra-useful IIA, while easing up causes them to switch back. Want to boss it at burpees? Don’t skip legs day.
05 MIND OVER MATTER
Finally, remember that sometimes it’s in your head. Is it that you physically can’t go on, or that you don’t want to? ‘Your level of motivation quite often determines how long you’re prepared to tolerate discomfort,’ says Cowan. ‘Having a goal, such as beating a friend’s rep count, will help you push harder, as will an inspiring instructor.’ Don’t underestimate the power of a playlist, either; the right tracks can lift your endurance by 15%.