The 21-Day Shred: Muscle Run Conditioning Challenge, Day 17

Day seventeen is both a fat-burning workout and a cardio endurance booster. We call it a “Muscle Run.” MEN’S FITNESS digital director Mike Simone demonstrates the execution of the workout. Scale the workout based on personal abilities.

DOWNLOAD The 21-Day Shred app for iOS to get the full training program, diet, and more. No iOS? No problem. Get a COPY of the PDF.

In between training cycles, or looking for more food options? DOWNLOAD your copy of The 21-Day Shred Cookbook, packed with over 75 muscle-making meals.

THE WORKOUT: Muscle Run, Day 17

Select a run of 1, 3, 5, or 7+ miles. Set a tracker on your phone to alert you at the .25 mile mark.

Sample Aggressive/Advanced Athlete:
5 mile run followed by 25 push ups, 25 situps, 25 squat jumps, and 25 crunches at each .25 mark.

Sample Beginner Athlete:
1-2 mile run followed by 10 push ups, 10 sit ups, 10 squat jumps, and 10 crunches at each .25 mark.

Sweatshirt: American Giant
Baselayer Tights: QOR Seamless Training Tight
Shoes: Mizuno Waverider 18

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