This is a variation of the basic exercise for developing back muscles and biceps. It is suitable for beginners.
Find a low crossbar or hold the TRX-loops.
Take a position so that your torso is parallel to the floor.
Keeping your torso straight, take a deep breath.
As you exhale, pull up until your chest touches the bar (or, if you use TPX-loops, bend your elbows as much as possible).
Pause for 1-2 seconds at the top.
As you inhale, return to the starting position.
Do not swing during the exercise and do not try to throw your body upwards.
To make the exercise more difficult, try not to place your feet on the floor, but instead keep them hanging. Bend your knees first, and then pull them to your chest.
You can also use a backpack with additional weights.
You can push your chest forward on purpose, and try to touch the bar with your chin.