Football is a game of strength, speed and power. But without conditioning, you wouldn’t be able to recover between plays and would quickly lose those essential qualities.

That’s why Rob Gronkowski prioritizes conditioning in his off-season training. He’s on the field for the vast majority of offensive plays, running routes, blocking hapless opponents and breaking tackles. Without a base of endurance, he wouldn’t dominate play after play.

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Gronk’s go-to conditioning workout is on a rowing machine. That’s why the Gronkowski brothers decided to launch the Gronk M1 WaterRower—so that other athletes could take advantage of the same product they use in their own workouts.

The Gronk M1 WaterRower features a water-resisted flywheel that offers butter-smooth operation. The harder you pull on the rower, the greater resistance the flywheel provides.

Here are three of Gronk’s favorite WaterRower workouts.

Intervals

Interval training is the single most effective and efficient way to improve your conditioning. The beauty of intervals is that you can push yourself near your max for a brief duration, because the subsequent rest period allows you a brief period of recovery, which trains both your short-term and long-term endurance.

Instructions:

• Row at max speed for 1 minute
• Rest for 1 minute
• Repeat for a total of 10 minutes

Aerobic Conditioning

Another go-to workout for Gronk and his brothers is a 20-minute “cardio” rowing workout. Although it’s not the sexiest type of workout, building an aerobic base is critical for football players and other sprint-based athletes. A solid aerobic base allows for faster recovery after an intense set of an exercise and between plays on the field.

The WaterRower is an ideal device for this type of workout because there’s no impact; you’re not beating up your knees from running. Plus, you are working your upper-body muscles in addition to your legs.

Instructions:

• Row at a steady pace for 20 minutes.

500-Meter Challenge

For an added challenge, find a partner and see who can row 500 meters faster. As you can see in the video above, Gordie Jr. and Chris Gronkowski take this challenge. It only takes a few minutes to complete, but it’s brutally difficult—and it’s a fun way to compete with a teammate.

Instructions:

• Time yourself with the rower’s computer or have a partner use a stopwatch.
• Row as fast as possible for 500 meters.

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