After some time, these workouts do no provide enough resistance for the abdominal muscles; therefore they do not help to improve. (abmachinesguide.com)
So what to do you do if you want to work your chest with enough resistance for muscle growth but the standard push - up is too easy? (fitstep.com)
Both of the thumb buttons are large and easily accessible, and every button feels good to click, offering just enough resistance. (tomsguide.com)