How much cardio do you need for heart health if you lift weights for hypertrophy?

Question from a Zolt member: 

I’ve been focusing on bulking up and building muscle through hypertrophy training, but I’m also concerned about my heart health. 

I’m wondering how much cardio I should include in my routine. 

How many sessions per week would you recommend, and how long should they be? 

I’m curious about the balance between moderate and high-intensity workouts too.

Also, should I adjust my cardio routine when I’m bulking versus cutting? 


Answer by Zolt:

Hey there! Great question about balancing cardio and hypertrophy. Before we start, you need to remember – the heart is ALSO a muscle. Just because you can’t see it doesn’t mean it’s not there. It’s arguably the most important muscle of the body, so it 100% SHOULD be trained!

For heart health, you don’t need to go crazy with cardio if your main goal is building muscle. The American Heart Association recommends at least 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous-intensity aerobic activity per week [1]. That’s your baseline for keeping your ticker happy.

Now, how does this look in practice?

  • Time per week: Aim for about 2-3 hours of cardio spread across your week.
  • Number of sessions: 3-4 cardio sessions a week is a good target.
  • Intensity mix: Try for 1-3 moderate-intensity sessions (where you’re breathing harder but can still chat) and 1-2 high-intensity sessions (where talking is a challenge) per week.

These recommendations align with the guidelines from the American College of Sports Medicine (ACSM) for maintaining cardiovascular fitness [2].

But here’s the kicker – these numbers can shift based on whether you’re bulking or cutting:

  1. Bulking: If you’re bulking, your body has more energy to recover, so you can handle more cardio at this point. 99% of gym-goers should not think too hard about the type of cardio they’re doing – they should just DO cardio. However, research suggests that excessive endurance cardio can interfere with muscle gains during a bulking phase [3]. You can read more about it here. Do note though, that is just one endurance study. If you’re running 10 miles a week, this probably doesn’t apply to you. If you’re running 50 miles a week… then muscle gain will definitely be tougher naturally.
  2. Cutting: This is probably the best time to do cardio, as it allows you to raise your TDEE (maintenance calories). You could increase to 4-5 sessions a week and generally go for efficient calorie-burning exercises, like running and swimming. High-intensity interval training (HIIT) has been shown to be particularly effective for fat loss while preserving muscle mass [4].
  3. Heart health doesn’t change much whether you’re bulking or cutting, so keep that baseline in mind.

As for the type of cardio, variety is great, but it’s not absolutely necessary. If you love running and that’s all you want to do, go for it! The key is consistency and enjoyment. That said, mixing it up (like combining running, cycling, and swimming) can help prevent boredom and work different muscle groups. A study in the Journal of Applied Physiology found that cross-training can improve overall fitness and reduce the risk of overuse injuries [5].

Remember, the best cardio routine is one you’ll actually stick to. Find what you enjoy and make it work for your schedule and goals. 


Sources:

[1] American Heart Association. (2018). American Heart Association Recommendations for Physical Activity in Adults and Kids. https://www.heart.org/en/healthy-living/fitness/fitness-basics/aha-recs-for-physical-activity-in-adults

[2] Garber, C. E., et al. (2011). Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory, Musculoskeletal, and Neuromotor Fitness in Apparently Healthy Adults: Guidance for Prescribing Exercise. Medicine & Science in Sports & Exercise, 43(7), 1334-1359.

[3] Wilson, J. M., et al. (2012). Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises. Journal of Strength and Conditioning Research, 26(8), 2293-2307.

[4] Boutcher, S. H. (2011). High-Intensity Intermittent Exercise and Fat Loss. Journal of Obesity, 2011, 868305.

[5] Tanaka, H. (1994). Effects of cross-training. Transfer of training effects on VO2max between cycling, running and swimming. Sports Medicine, 18(5), 330-339.