When someone says “cardio”, what’s the first thing that comes to mind? A treadmill? An elliptical? Spin Bike? Inhumane torture? All of those will improve your cardiovascular endurance (minus the whole torture thing). However, they do not define what cardio is.
Anything that gives you a cardiovascular response (for example a quicken heart rate, or heavy breathing) and cardiovascular exercise is technically cardio.
That being said, can weight training replace cardio?? According to Dr. Eric Helms and Dr. Mike Zourdos in their October edition of “MASS”, (a fantastic series of free articles they publish that I will link it HERE) there is strong evidence suggesting that cardio can in fact be replaced. The article is a review of a 2017 study from Androulakis-Korakakis et al. titled The effects of exercise modality during additional ‘high-intensity interval training’ upon aerobic fitness and strength in powerlifting and strongman athletes.
The Study itself establishes a few key points;
HIIT (High Intensity Interval Training) cycling and HIIT lifting (squats and deadlifts for high reps with short rest periods) seem to have similar effects on strength.
HIIT cycling likely improves aerobic conditioning more than HIIT lifting does.
HIIT cycling would probably be the more judicious choice for coaches and athletes, as it’s likely safer and it allows for greater flexibility when structuring a training week.
While cardio is notoriously despised among most strength athletes, it has a plethora benefits that should be observed, such as increased work capacity (ie more volume) reduction in the amount of time between sets that you need to recover (catch your breath). While it is seemingly true that cardio takes away from strength gains as opposed to strictly strength training, it is referenced that a lighter weight (approximately 60% of the groups single rep max) being used at higher reps (10-15) can mitigate the interference effect.
The study took two groups of male strength athletes both experienced in weight training and similar ages. One group worked with a modified percentage of weight for higher reps while the other group did a high intensity interval training session twice per week on a spin cycle.
Some points to note:
HIIT cycling affords you much more flexibility in your training than the HIIT squats and deadlifts.
HIIT cycling is hard, and the first time you do it, you may be a little sore the next day, but you’ll adapt to it quickly.
It may hinder recovery from squatting or deadlifting a bit, but the impact will likely be manageable (especially if you’re not either very lean or in a big calorie deficit). However, high rep squats or deadlifts with 60% of 1RM and short rest between sets is always going to be brutally hard.
In essence, getting your HIIT work from squats or deadlifts gives you smaller aerobic benefits and necessitates a lower average weekly training intensity, decreasing the amount of highly specific strength work you can manage. Safety also needs to be considered. Fatigue when cycling is perfectly safe. Specifically chasing metabolic fatigue during high rep squats and deadlifts, on the other hand, increases the risk of technique breakdown and putting your body in compromised positions that could increase injury risk.
The Big Takeaway
If you’re a strength athlete adding HIIT to your program, this study indicates that cycling may be a more judicious choice than high rep, short rest squats and deadlifts. The additional squats and deadlifts didn’t provide an advantage for strength development, and the HIIT cycling led to larger increases in aerobic fitness. Moreover, from a practical perspective, it’s easier to modify a training program to accommodate HIIT cycling, and HIIT cycling is likely the safer option as well.
– Scott
