Medicine ball crunches

According to the study, the bicycle crunch was the most effective exercise when analysing the muscle activity in the abdominals. To complete a bicycle crunch, lie on your back with your lower back pressed into the ground, bring your knees in towards your chest and lift your shoulder blades off the ground.

Studies have revealed that there can be greater core muscle activation doing crunches or sit-ups on a bosu ball compared to a flat, stable surface . And if you think about it, this makes sense… When most people do ab work, they don’t use very much weight, and tend just to do a higher number of reps.

Putting your hands or feet on a Swiss ball during a plank exercise is brilliantly effective ; as well as trying to remain rigid, you’ll be fighting the tiny movements of the ball. Same if you balance your feet on the ball and do press-ups.