Hold a 4-minute plank in just 5 weeks – no gym, no equipment, only a few minutes a day. Plank Challenge is a proven, progressive program that takes you from beginner to a 4-minute plank, step by step. HOW IT WORKS - Train 4 days, rest 3 – your muscles get time to recover and grow stronger - Progressive plan designed to prevent injury - Clear daily instructions and progress tracking - Bonus: build from 1 to 100 push-ups at your own pace WHY PLANKS? Planks strengthen your abs, back and arms at ...
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