Your Body at 45 Is Not Your Body at 25

After age 30, you lose about 3% of your muscle mass each decade if you don't train to keep it, a stat from Harvard Health that Clayton references. It's a big reason people show up at 60 unable to do things they used to.VO2 max (how well your body uses oxygen) and bone density both start trending down around 40. You get winded easier and your bones get thinner, but resistance training, jumping, and landing push back on it.Recovery takes longer as you age, partly because blood flow to the muscles slows down. A tweak that bounced back on its own at 25 now needs real attention.The infinite game reframe (from Simon Sinek's book The Infinite Game): stop training to win today's workout and start training so you're still capable at 65 and 85. Live like a Prius, not a race car.Reset your PRs. Wipe your personal records every decade, every five years, or even every birthday so you're measuring against who you are now, not who you were at 35.How to know you're doing enough: show up at least two days a week (more if you're not active outside the gym) and do something that challenges you that day, even if it wouldn't have challenged 20-year-old you.A heavy day isn't a max day. Bridgett walks through coaching a full-stop deadlift session and resetting expectations, including an athlete who lost 100 pounds and had to rethink her numbers because losing the weight changed the lift.