What happens if you lift weights but don’t do cardio?

I used to train with this guy at the gym who had all the markers for strength – bulletproof chest, bulging biceps, six pack abs. Your standard Men’s Health cover model.

I asked him one day whether he did any cardio.

“What?” he replied with a confused look. “I don’t speak Spanish”.

While obviously tongue in cheek, his response is representative of the majority that lift weights. “Cardio will destroy your gains” is the common refrain.

This was also my philosophy for the first 10 years of strength training. That was until gyms closed during lockdown and I discovered running.

Complementing this with home workouts for a year yielded surprising results – muscle mass was maintained but there was more density and definition in my physique (roundabout way of saying I looked more ripped).

I also noticed more energy, better sleep and recovery and just a general vitality that wasn’t there before when just lifting weights. Now cardio is an integral part of my workouts.

So what happens if you lift weights but don’t do cardio?

You’re still considered a fit individual.

I felt strong and confident when I was just lifting weights. Strength training builds muscle mass & bone density which is critical for general health and especially important as we age. So definitely keep this up.

The question that needs answering though is - why aren’t you training cardio?

If it’s because you think it will “destroy your gains” then think again. As long as strength training is still your primary workout, incorporating a day of cardio will not hinder but enhance your goals.

Your ability to recover better will also allow you to train with a greater intensity in the gym which leads to more muscle gains.

A sample training week could look like this:

Day 1: Upper Body

Day 2: Lower Body

Day 3: Easy Run

Day 4: Upper Body

On the other hand, if the very thought of cardio is repulsive then don’t stress too much about it. The best exercises are the ones we can do on a consistent basis so if cardio isn’t something you enjoy then its ok not to do it.

But if you’ve never tried cardio training, I would suggest to give it a go.

From my experience, it doesn’t destroy your gains (it enhances it) and comes with a host of other benefits including improved heart & lung health, energy and better recovery.

All of this supports your goals in the gym.