For metabolic health, does cardio or strength matter more?
|
When we think of the benefits of exercise, we tend to put resistance and aerobic training into different “buckets”:
There is some truth to this of course. At the extremes, a bodybuilder looks very different to a marathon runner, after all. But is the distinction really that clear - especially for the health benefits we can’t see? A 2026 systematic review and meta-analysis comparing aerobic and resistance training head-to-head delivers new insights from a cardiometabolic health perspective. This matters because poor cardiometabolic health underlies many of the chronic diseases that cause disability and premature death - from heart disease and stroke to type 2 diabetes and kidney disease. And the results suggest that while some benefits differed between the two exercise types, there was more overlap than you might think. So, where did exercise type matter - and where did it not? What did the study actually compare?The analysis included 23 randomised controlled trials in 1,184 adults aged 30-70 with both type 2 diabetes and obesity (or “diabesity”). So, these findings apply specifically to a population with compromised cardiometabolic health. Each included study directly compared the influence of aerobic and resistance training interventions (ranging from 8-52 weeks) on:
The researchers then pooled these head-to-head comparisons to determine where one exercise type had an advantage over the other. And there were some clear differences. Where aerobic training had the edgeTo some degree, yes. When compared head-to-head after the interventions, aerobic training showed advantages for:
These findings aren’t entirely surprising based on what we know about the specificity principle with exercise. Because aerobic training specifically challenges the cardiovascular and oxygen-delivering systems, it makes sense cardiorespiratory fitness was higher. The lower blood glucose levels after aerobic training was particularly relevant for this population too, given their type 2 diabetes. But the specificity worked in the other direction too. Where resistance training had the edgeAgain, this part wasn’t all that surprising. After the training interventions, resistance training was superior for:
This makes sense given mechanical loading is a key stimulus to build or maintain lean tissue, and this stimulus is far greater with resistance training. On the other hand, the finding that body fat percentage was lower after resistance training versus aerobic training may have not been what you expected. Most people associate fat loss with aerobic training and energy expenditure - but resistance training can have important fat-lowering effects too. It’s another reminder that what happens on the scale doesn’t tell the whole story. But here’s where it gets interesting...Sure, the benefits of aerobic and resistance training were somewhat distinct. But the most important finding for wasn’t how they differeed, but how much overlap there appeared to be. For many outcomes, there was no statistically-significant difference between the two modalities, including:
That’s pretty notable given we usually think of these modalities as having completely different health effects. Importantly, “no statistically-significant difference” does not mean the two exercise types had equivalent effects - only the analysis didn’t find clear evidence one was better than the other for those outcomes. Even still, the results suggest some benefits are more specific to exercise type, while many cardiometabolic benefits appear to overlap. So the natural question is: if either can provide such broad benefits, do we really need both? So is doing both really better?Ideally, probably yes. Other long-term studies generally show combining both exercise types leads to the best health outcomes, including a lower risk of multiple chronic diseases and mortality: It’s important to note this new analysis didn’t compare doing both types to either alone - so it can’t say whether doing both was actually superior. But the results do hint at why combining them makes sense from a benefit perspective. Aerobic training covers the adaptations that resistance training doesn’t optimise, and vice versa. In that way, doing both may give you a broader range of adaptations - not only that benefit cardiometabolic health, but your ability to stay mobile and independent, too. But that doesn’t mean only doing one isn’t enough, either. What this means for your trainingThe main takeaway from this study is an encouraging one. Because it suggests that if you love running or cycling, you can still get important benefits if you aren’t doing any strength training. Likewise, if you’re into lifting but rarely do any formal “cardio”, you’re probably getting more cardiometabolic benefit from your training than you might think. It’s tempting to think that if we’re not able to do the “ideal”, then it’s not worth doing at all. But studies like this remind us that doing something, even if it’s only one type of exercise, often leads to more benefits than we might think. Doing both aerobic and resistance training may lead to the broadest benefits. But doing either probably gets you most of the way there. Thanks for reading! Until next week, Jackson
If you've got a moment, I'd love to hear your thoughts on this edition of The Weekly Exerciser. Send me a quick message or email - I'll reply to every one! PS: Did someone forward you this email? You can sign up to The Weekly Exerciser here. IMPORTANT:The information contained herein is of general nature only and does not constitute personal advice. You should not act on any information without considering your personal needs, circumstances, and objectives. Any exercise program may result in injury. We recommend you obtain advice specific to your circumstances from an appropriate health professional before starting any exercise program. |
The Weekly Exerciser
A weekly newsletter with actionable tips to make exercise easier.