Usage method:
1. (1~5) days, 5 minutes a day, up to 2 times a day
2. (6~10) days, 8 minutes a day, up to 2 times a day
3. (11~15) days, 12 minutes a day, up to 2 times a day
4. (16~20) days, 16 minutes a day, up to 2 times a day
5. (21~25) days, 20 minutes a day, up to 2 times a day
6. months of exercise time
