How Much Lifting is Enough? How Much is Too Much?

How much resistance training do you actually need, and is there a point where more stops helping? We trace the "lift weights twice a week" recommendation back to the 1989 study it came from, which found that three days beat two, and to the citation loop that turned it into a guideline anyway. Then we go through the evidence on whether lifting is dangerous, including the heart, injury rates, and the J-shaped mortality curve, and work out where the dose-response actually saturates for strength, muscle mass, bone mineral density, and how your body handles fuel.
The short answer is that almost every number in this literature marks where a benefit starts, and very little of it goes far enough to show where a benefit stops. We finish by writing the resistance training guideline the way we think it should be written, with target outcomes, a training dose, and testable targets.
Timestamps
00:00 Where the "lift weights twice a week" rule came from
04:18 What actually counts as resistance training
06:56 Does lifting make your heart wall thicker
15:34 Anabolic steroids and the heart
19:16 Injury rates and cardiac arrest at the gym
22:03 How the lifting J-curve got made
28:05 ACSM audits its own recommendation
31:11 Strength: where the plateau actually sits
35:49 Why grip strength can't answer this
41:43 Muscle mass versus muscle function
44:50 Bone, and the turkey wing that settled the dose
49:50 Fuel handling, insulin sensitivity, and the clock
1:00:46 The 2018 guidelines, and how I would write them
Resources
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