Here is a handy trick to build muscle for free without a device with our smart exercise .
Sit in a chair without an armrest. Place your hands on either side of the seat, arms straight, shoulders high and back straight.
Once in this position, raise your legs about 10 centimeters and contract your abs.
Hold for 20 seconds then release.
To thoroughly build your abdominal muscles, repeat this exercise at least 10 times in a row with a 10-second break between each repetition.
Do this free exercise every day and after a few weeks you will have a belt of abs at the top.
Exercising at home or in the office is the best way to save money.
You won't pay for a gym and won't need to buy weight machines.
For more exercises you can do without a device, check out this tip.