Why is it important to keep our back straight while performing a hamstring stretch

Because when you arch your back it puts stress on the spine. you’ll probably start having lower back pain : ( hopefully this ! : )

People who utilizes the progression principle will ensure their exercise program increases in frequency, intensity, time, and type. the changes need to happen gradually in order to ensure they make gains in their fitness program. a person who doesn't utilize the progression principle can still gain health benefits from exercising, but will not continue to improve in cardiovascular fitness.