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With summer ending, you may not need your six-pack for the beach -- but maintaining that fit physique is an all-year commitment.

Four-time Super Bowl champ Rob Gronkowski and "The Bachelorette" fan-favorite Jason Tartick were tapped by Amazon to share their ultimate fitness picks -- and it's clear these boys know what it takes to get buff.

From workout equipment to supplements and trackers .... here's what they suggest!

Fitbit Inspire 3

Best place to start your fitness journey is with a Fitbit Inspire 3 , which will help you track your progress every step of the way ... literally!

This fitbit has all-day activity tracking, monitors your heart rate 24/7, features 20+ exercise modes, autom

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