Original sentence: Commonly, weight training is performed as an anaerobic exercise, in that the weight being lifted is heavier than can be raised by aerobic muscle fibers alone.Weight training using a low number of repetitions and relatively high weight is primarily anaerobic, while using lower weights and higher repetitions can be substantially aerobic7
Edited sentence: Most often, weight training is performed as an anaerobic exercise, in that the weight being lifted is heavier than can be raised by aerobic muscle fibers alone.Weight training using a low number of repetitions and relatively high weight is primarily anaerobic, while using lower weights and higher repetitions can be substantially aerobic.Weight training using a low number of repetitions and relatively high weight is primarily anaerobic7, while using lower weights and higher repetitions can be substantially aerobic