Cardio and strength training: compatible?
6 min read
'Cardio kills gains': a phrase that discourages many lifters from moving more. The truth is nuanced. Well dosed, cardio is an ally of health and even of strength training. Poorly managed, it can slow muscle gain. Here is how to find the right balance.
Cardio does not destroy muscle
Doing cardio does not melt your muscles. What can hurt muscle gain is excessive cardio combined with a large calorie deficit: the body then lacks the energy to build. But a few cardio sessions a week pose no problem and improve your recovery and heart health.
Cardio even has benefits for the strength trainee: better endurance between sets, faster recovery, and easier weight management. Demonizing it is a mistake.
Matching cardio to your goal
During a bulk, keep cardio moderate (2 to 3 light sessions a week) for health without digging a deficit that would hinder muscle building. During a cut, cardio becomes a valuable tool to raise energy expenditure and speed up fat loss.
The type of cardio matters little: brisk walking, cycling, running, rowing… choose what you can sustain. Daily walking, often underrated, is one of the best tools to burn calories without taxing recovery.
Organizing both well
If possible, separate intense cardio and strength training: do them at different times of day, or on different days. Stacking hard cardio just before legs can hurt your strength performance.
If you must combine them in the same session, do strength training first, when fresh, then cardio afterward. That way, the training most important for your goals gets your maximum energy.
The interference effect: myth or reality?
The idea that cardio 'blocks' gains comes from the interference effect, a real but modest phenomenon: at very high volume, cardio can slightly blunt strength and hypertrophy signals. For most trainees, a few sessions a week are far from that threshold and have no negative impact.
The type of cardio also matters: running, with its impact and eccentric component, tires the legs more than cycling or rowing. If you stack cardio and legs, favor low-impact cardio, or space them out in the week.
Frequently asked questions
Should you do fasted cardio to lose fat?expand_more
Fasted cardio offers no magic advantage for fat loss: what matters is the total daily calorie deficit. Do your cardio whenever you feel best, fasted or not — the key is sticking with it over time.
How much cardio per week?expand_more
For health, aim for about 150 minutes of moderate activity per week. For a cut, you can add sessions as needed, without overdoing it. Always keep enough energy for your strength sessions, which remain the priority for preserving muscle.
Running or cycling if I lift?expand_more
Cycling (or rowing) tires the legs a bit less than running, whose impact and eccentric component cause more soreness. If you love running, it is perfectly fine in reasonable amounts; otherwise, just choose the cardio you enjoy and can sustain over time.
Put this guide into practice
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