Jack knife

08

How to do it: Adopt a press-up position with both your feet on a gym ball. Keep a relatively neutral spine position, otherwise your arms will do most of the work and quickly fatigue. Keeping your feet on the ball, pull your knees towards your chest, then return to the start.

Core value: “This is a hugely demanding core exercise that will target your hip flexors, rectus abdominis, obliques and upper-body stabilisers. It will particularly help those who ride in an aggressive position on their time trial bike.”

Dose: 2 to 3 sets of 6 to 8 reps, but focus on form over volume

Level: Advanced