“Cardio kills gains” is one of the most persistent gym myths. We break down the interference effect research and show you how to program cardio without sacrificing muscle growth.
In gym culture, “cardio kills gains” might be the single most repeated belief. Plenty of lifters skip cardio entirely during a bulk — some won’t even glance at a treadmill.
This idea traces back to the interference effect, first described by exercise scientist Robert Hickson in 1980. His study found that subjects who combined high-intensity endurance training with strength training saw smaller strength gains than those who only lifted weights.
But does a study from over 40 years ago really apply to the average gym-goer today?
Over the past decade, numerous systematic reviews and meta-analyses have revisited this question. The results may surprise you:
A meta-analysis covering 43 studies and 1,090 subjects found that concurrent training (cardio + resistance training) produced no significant difference in muscle hypertrophy compared to resistance training alone.
A 2021 meta-analysis published in Sports Medicine reinforced this finding: concurrent training showed no significant disadvantage in maximal strength or muscle hypertrophy compared to resistance-only programs.
I’ve started adding 20 mins of LISS after lifting and my recovery is much better.
Would this be too much for someone already doing 5 days of PPL?
Is this suitable for a ‘hardgainer’ or will it burn too many calories?
Latest Post: The Science of Sequencing: Should You Sauna First or Cold Plunge First? Our newest member: Josh Sutton Recent Posts Unread Posts
