This comprehensive seven-day program combines intense workout sessions with strategic ... Research indicates that HIIT sessions ranging from 20-30 minutes can produce comparable or superior ...

Crush your core with this quick and effective 5-minute abs challenge. No equipment needed, just your bodyweight and determination!

The program includes HIIT workout days, active recovery days with optional steady-state cardio or yoga, and a group fitness day ... Each challenge workout takes 20 minutes or less, and each ...

The workout featured a warm-up, a four-exercise core circuit, and a cooldown. Get in, get out, get on with the day. Jennifer Nied I kicked off my first week of the challenge right after returning ...