Another Tabata Interval

The interval consists of hanging knee raises and walk out plank-ups. Start by doing as many hanging knee raises as you can in 20 seconds, take 10 seconds to rest, then do as many walk out plank-ups as you can in 20 seconds. Take another 10 seconds rest and then repeat the cycle 3 more times for a total of 4 minutes. Try to do as many as reps as you can in the first round and then try to match or better those numbers every round after!