It’s a common myth that “cardio kills gains”. However, the truth is that cardio won’t kill your gains, rather, poor programming will. This doesn’t come as too much of a surprise, after all, plenty of people fail to see good results because of poor programming, lack of recovery time, and not really having specific goals in mind. Here’s what we do know about cardio and hypertrophy.
First of all we have plenty of anecdotal evidence for the ability of cardio not to interfere with hypertrophy. The above image is just one of many examples, and I can remember off the top of my head a few different examples of cyclists with huge legs. There are also plenty of images showing the difference between sprinters and distance runners in terms of their physiques, and sprinters are often a lot more jacked. Point three - have you seen some of those football players out there?
Of course, we also have plenty of anecdotal evidence in the other direction for people with plenty of cardio and nooooo gainnzzz. But the existence of cardio heavy athletes with quite a bit of hypertrophy should at least be proof that it isn’t impossible to do both, even if it isn’t as commonly seen. Further, maybe we should ask ourselves, “what is it about sprinting and cycling that may make them different from other cardio modalities?”
Surprise surprise, sprinting is anabolic. (It’s anabolic bro. Science says so.) It’s also typically better for weight loss than steady state cardio since it scales a lot better, and that means more fat loss plus more muscle. Doesn’t that make sense anyway? Lifting a weight for a high rep range is similar to traditional steady state cardio, while lifting for a few reps is best for strength and muscle - sprinting places similar energy demands on the body. Sprinting is the “8-12 repetitions” of running, with steady state being the “30+ repetitions”. Further, while there are plenty of individual differences between sprinters, olympic lifters, and powerlifters, the three are “similarly strong”. Lots of good strength and conditioning coaches now advocate a few days of sprinting a week to lean up before a competition, since this seems to best coincide with bodybuilding goals. Plus it saves time. Thus, bodybuilders - sprinting may be for you.
Now what about cycling? We know that Bruce Lee used cycling as his primary form of cardio, and if you don’t know already, me and Bruce are like, such soul mates. It would appear that we also know that cycling, when combined with a traditional strength training program, leads to more gainz than either alone. There is a downside - RFD is reduced in concurrent cycling/strength training, meaning elite strength athletes will see their strength worsen as a result. However, in untrained subjects who have plenty of other variables to improve before RFD becomes a major factor, a net strength gain will still be seen. So it sort of makes sense that sprinting syncs up well with hypertrophy, for reasons I’ve stated above. But why does cycling lead to better gains?
Well how about this meta-analysis, which points out that “results indicate that interference effects of endurance training are a factor of the modality, frequency, and duration of the endurance training selected.” So what exactly is this science stuff telling us? Mainly that it’s largely what you’re doing and how long you’re doing it that matter. Running a marathon right before a strength training session, for example, will obviously sap you of energy and prevent you from gaining muscle, but fifteen minutes on a bicycle won’t.
Impact is a huge variable. Running is a high impact activity because it involves lots of forces, like taking a hammer to your feet over and over. Too much stress interferes with hypertrophy, but there are plenty of modalities that cause less stress. Ellipticals and cycles, for example, involve a lot less striking force and therefore a lot less impact. You can also remove the impact from running by progressing it with other variables than speed. Toss on a heavy weight vest, crank the incline way up on a treadmill, psych yourself up by imagining climbing mount Everest, and you’ll get a good cardio workout that doesn’t have a lot of impact on recovery. (Or if you’re in it for the lulz, get a good backpacking backpack and put weight plates in it. Watch reactions as people stare at you in the gym.)
Recovery is another huge variable. You can still combine resistance and endurance training so long as you’re programming intelligently and not doing too much at once. Alex Viada of Complete Human Performance personally boasts a 700lb squat and a 4:15 minute mile, two feats that are both extremely impressive. In addition to being totally jacked and rather photogenic, Alex advocates careful recovery programming as the key to successfully combining the two. Doing too much without enough recovery is a sure ticket to losing gains.
Of course, in the strength community this isn’t exactly news. Strength coaches have advocated for years for the training of GPP, or general physical preparedness. While the direct meaning is that you shouldn’t neglect more generalized training alongside the specific stuff (wait, was crossfit right the whole time???), this is typically code for “wait, what do you mean you aren’t doing cardio, son?” GPP advocates also like to champion sled/prowler work, which is notably low impact and can be loaded up pretty heavy. The benefits of GPP are obvious - better cardiovascular system means better work capacity, which means better energy management and more maximal strength.
In short, cardio doesn’t kill gains. Long distance running can kill gains, but only if you’re not planning intelligently enough. High impact activities like running have the most potential for interference, so reduce impact forces by switching your cardio modality to something slower but equally as challenging. Sprinting is unique in that it mimics the activity of strength training in cardio form, making it anabolic. Now go out there and get swole.
As always, we stand on the shoulders of giants. I am not a scientist, nor do I possess a degree in an exercise science related field. Much of the research of which I am aware I have been alerted to by people more scientifically minded than myself, since I spend half my time either working out or watching Netflix naked. Information being free, I have no obligation to provide credit to my sources, but I feel this is the only decent thing to do.
In this article I would like to thank Greg Nuckols for being an all-around bro, but also for recently getting onto a cardio and lifting kick. Some of his numerous articles on the subject can be found here, here, and here.
I would like to thank Bret Contreras and Chris Beardsley for running the Strength and Conditioning Research Review, without which I would probably have given up hope on life a long time ago.
Lastly I would like to thank Alex Viada for being living proof of the value of all this research. Aside from his website you can find articles he’s written on the subject at Juggernaut Training Systems (cited above) and Greg’s own site.
This doesn’t really fit anywhere in the above article but is vaguely relevant - suggests order of training may be very important, with the final activity performed in a day being the one the body has the best response to. Do your cardio first, and your lifting after! Not proof though, since it’s on rats. Requires further study, but is quite interesting.