The sit up, unique bodyweight exercises difficulty rating for one rep 2 out of 10
Average time to master, straight away.
This old faithful has been discarded in recent years for crunches which are now the most popular basic exercise for the abs, however, I feel the sit up still has a place in any training routine as the coordination necessary to do them correctly is a great way to focus the mind on working the abs and they are also a good exercise to prepare for the more advanced core exercises.
To begin, lie on the floor with your legs bent so that your knees are pointing directly upwards, your feet should be flat on the ground so that both heel and sole are on the floor and I recommend you place your feet under an object such as a bed, settee or weight plate to keep them from moving.
From there, place your hands behind your neck to help support it throughout the movement and then as you breathe out slowly lift your head, shoulders and torso towards your knees in one smooth movement using only your abdominals to power you up.
Once you have risen a foot or so of the ground you will feel the tension leave your abs and that is as high as you need to go (Any further does not work the abs and can cause lower back problems)
Pause at the top of the movement for a second and then lower yourself back down using your stomach muscles to control your decent until your hands are a couple on inches from the floor and then repeat.
Note, by stopping your hands a couple of inches from the floor you will help keep the tension on the abs at all times.
Your hands should only support your neck and not help you lift up as this will almost certainly strain your neck.
Expel the air powerfully from your lungs as you lift up to give you far more power in this exercise (Similar to the power shown by martial artists in breaking techniques).
To get the most out of this exercise it is essential that you concentrate on using only your abdomen throughout the movement.
Once you find sets of 15 reps easy move on to more advanced exercises such as the dragon flag or full ab wheel rollout but still include sit ups in your routine from time to time as they help focus the mind solely on the abs during core training.