Cardio

Hi Jordan and Austin,

I have a couple of cardio questions:

  1. What’s the upper limit for cardio before it negatively impacts resistance training?
  2. If my goal is to reduce my resting heart rate, would 30-40 minutes 3x/week of ZONE 2 be sufficient to get most of the benefits in this regard, or would 60 minutes 3x/week be a lot better? I’d also do a session of hiit fortnightly.

Thanks, Eric

Erik,

We discussed the interference effect, e.g. cardio negatively affecting gainzZz from resistance training, in podcast episode 237. You can listen to that here. A brief quote describing the most recent meta-analysis on the topic:

“Concurrent aerobic and strength training does not compromise muscle hypertrophy and maximal strength development. However, explosive strength gains may be attenuated, especially when aerobic and strength training are performed in the same session. These results appeared to be independent of the type of aerobic training, frequency of concurrent training, training status, and age.” Schumann 2022

There is no singular upper limit for cardio, as this has to do with the individual’s current training tolerance, recovery resources, and so on. I think the majority of people can do at least 150-minutes per week with no significant effect on strength adaptations.

I do not think either scenario is enough conditioning to get “most” of the cardiorespiratory fitness-based benefits available to you, though I’d favor 180 min/wk over 90. The current guidelines recommend 150-300 min per week as a minimum target. We also know that there’s a dose dependent relationship between health and cardiorespiratory fitness, where more fitness correlates to better health. While this isn’t linear, I suspect somewhere closer to double the guidelines’ recommendations is more likely to “max out” someone’s general cardiorespiratory fitness development vs 90 or 180 minutes as suggested here. Logistically, that may not be possible and in that case, I’d go with the most you can do per week in this scenario. I would skip HIIT here as well.

-Jordan

Jordan,

Thanks. So to summarise, 1 hour zone 2 cardio done 3x/week is unlikely to see significant resting heart rate reduction over time, but is better than nothing, and you’d suggest not doing hiit in this scenario. Is this correct?

I was trying to be more careful with my wording. I do think engaging in regular conditioning work will likely lower resting heart rate in individuals proportionate to their improvements in fitness, which is going to be proportionate to training volume, existing fitness level, genetics, etc.

Maximal resting HR reduction will likely require substantially more conditioning volume than proposed here, so to get the most HR-lowering benefits, I suspect more volume is better.

I do not think HIIT is a good use of training resources in this setting, correct.

Thanks for clarifying Jordan. My goal is to reduce my resting heart rate by 5-10 beats, bringing it into the 50s per minute (currently 61-64 bpm), so I hope 3 hours of steady state may get me there in time.

Yea, I think that’s likely. If we were talking lower than that or a much higher VO2max for example, I think that is likely to take more. This should be fine IMO.

Many thanks, Jordan.

Hi Jordan,

If I’m doing 3 x 1hr per week of zone 2 running (74-81% MHR), would you recommend periodic “deloads” every month or so whereby I reduce training time to 50% (3x 30min per week) for a week?

Eric

I probably wouldn’t consider a deload to be beneficial for long-term fitness or health until volume and/or training load is higher, maybe double what you’re currently doing. I don’t mean that in any sort of negative way. Rather, I think 3hr/wk conditioning is about the same as 2x/wk lifting, meaning its difficult to overreach.

Many thanks Jordan! Cardio training that I can do consistently week after week without having to make changes and overthink it is just what I want.

Heh, me too. Carry on.

Hi Jordan,

I’ve been getting heartburn and burping a lot whilst doing running training despite waiting until 1.5 hours after eating breakfast before running.

Should I run before breakfast (fasted) instead? And would this affect my strength/hypertrophy training?

Would first try a smaller meal and/or a liquid meal prior to conditioning training.

I may not have a complete picture of what your training setup is, but I am assuming you’re not doing your conditioning prior to your lifting in the same session. Therefore, I don’t think how you fuel your conditioning is likely to have much effect on strength or hypertrophy.

Conditioning is Tues, Thurs, Sat, while lifting is Mon, Wed, Fri.

My concern was that doing a fasted cardio session the day after a lifting workout would reduce the hypertrophic response to the lifting.

I don’t think so and have no concerns about it!

Great, thanks Jordan!