calf muscle and quadraceps
Chin-the-bar and Push-Ups.
Using a stopwatch to count the number of pull-ups performed.
You can stretch out your muscles, build muscles by doing sit ups, crunches, push ups, etc. I myself use one in morning and at night to do my crunches. The lift off the ground puts more stretch to your muscles so it benefits using one.
Yes, you get abdominal muscles.
The key would be to strengthen muscles. Muscles support bones.
you step up then down on a bench
No.
Neither is better, they work different muscles.
104 calories are burned by doing only 12 minutes of step ups but I don't know about the number of step ups that is, hope I helped xoxoxoxoxox
Biceps, Triceps and the lats mainly. Also Muscles found in the lower back and the thighs
the muscles required to take a step backward(:
Abdominal muscles, among others.