water filling a glass cup

Slight dehydration, just 1.5% of your total body mass, can inhibit max strength by 6%.

Did you know that water can make you stronger? A whopping 70% of your muscle tissue is water. If that isn’t a dead giveaway of water’s importance on strength, I’ll share a few more insights.

One study that looked at the effects of water on strength output found that, in a slightly dehydrated state, a shortage of only 1.5% of your total body mass, you can only lift 94% of your maximum.

Now, that may not seem like a huge decrease at first, but let’s explore what that means. In an intense 45-minute workout, the amount of reps you can do with any given weight is directly proportional to your 1-rep max in the movement.

Everyone is a little different, but for example, if one’s dumbbell military press 1-rep max is 60 lbs in each hand, then they can likely do 15 reps with 40 lb dumbbells. If the 1-rep max (120 total pounds) is reduced by 6% to 112.5 lbs due to slight dehydration, they have to reduce the weight to 32 lbs per hand to get the reps. That’s a reduced work output of 16 total pounds per set.

Over 3 working sets, that’s 48 fewer pounds hoisted. Now that’s just one exercise. Over a 12-exercise full body workout, for example, with that being the average weight (not unreasonable considering the demands of squats/deadlifts/chest press, rows etc), that’s 576 pounds NOT lifted!

That makes a big different in total work output, a big difference in total calories burned, a big difference maximum strength gained, and a big difference in excess post-exercise oxygen consumption (or EPOC – the “after-burn” effect that can continue for 24-48 hours).

So stay hydrated, maximize your exercise sessions, get leaner, get stronger, and get it all faster.