9 Ways to Tell If You’re Exercising Enough

What it means: It's probably time to add more weight. "You should barely be able to squeeze out that last rep," says Rillinger. If you're not sure you can do one more, try she says. If you fail, that's OK, and is a sign you've reached your limit!

How to adjust: Pick up free weights that are two to four pounds heavier than what you're used to, suggests Bulvanoski: "It can help burn more calories, take your sculpting routine to the next level and get you results faster."

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