Cardio or weights: what's better for health benefits?

Read time: 4 minutes

What’s better: cardio or weights?

It’s an age-old question.

Well, maybe not really…

Most of us associate cardio (or aerobic training) with getting “fitter” and resistance training with getting “bigger” (muscles).

But let’s face it, not everyone cares about these things.

So how do they stack up when it comes to general health benefits?

The answer might surprise you.

Aerobic versus resistance training for health

Many link the health benefits of exercise with aerobic training.

We’re talking about things like reduced blood pressure or blood sugar, or a lower risk of chronic diseases such as heart disease or diabetes.

But do we have to walk, run, ride, or swim to get these benefits?

Or can pumping some iron help too?

Contrary to what most people might think - science says it can.

This is nicely summed up in this figure:

It shows the reduction in the risk (known as a hazard ratio) of all-cause mortality and various chronic diseases with:

Aerobic training alone (in blue)
Resistance training alone (in red)
And the combination of both (in yellow)

The effects of each are shown relative to no exercise, which is assigned a hazard ratio of 1.

As you can see, the benefits are greatest with the combination of both aerobic and resistance training.

But what’s also clear is either alone has pretty similar benefits across the board.

The underappreciated health benefits of resistance training

There’s a few lessons we can learn from these findings.

The first is the surprising benefits of resistance training on curbing our risk of all-cause mortality and a range of chronic diseases.

This aligns with the growing evidence for the general health benefits of lifting weights.

Engaging in resistance training has been linked to:

Reduced fat mass
Improved cognitive function
Reduced mortality from cancer
Better glycaemic (blood glucose) control

These benefits are on top of more well-known upsides of resistance training.

Things like improved:

Muscle mass
Strength and power
And reduced falls risk

What this all points to is the general benefits of aerobic and resistance training are actually more similar than different:

The “forgotten” part of the physical activity guidelines

The traditional focus on the health benefits of aerobic training has infiltrated our physical activity guidelines and messaging.

You know, the ones that say each week we should do:

150 minutes or more of moderate-intensity aerobic activity (or 75 minutes if vigorous intensity)
2 or more sessions of “muscle strengthening exercise”
And for older adults, balance and flexibility exercise on 2 or more days

Historically, these guidelines focused only on aerobic training. Only in the last 15 years or so has resistance training been included.

But despite the comparable benefits, there’s still a very wide gap between the proportion of those who meet aerobic compared to resistance training guidelines.

As the figure below shows:

About twice as many adults aged 18-64 don’t meet the resistance training guidelines (72%) compared to the aerobic training benchmarks (35%)
And in those aged 65+, the proportion who don’t do any resistance training (94%) is about three times higher than for aerobic training (35%)

Sure, there’s many reasons for the discrepancy in participation between aerobic and resistance training.

But these figures suggest resistance training is still very much seen as a secondary aspect of general physical activity.

The “forgotten” part of the physical activity guidelines, if you will.

That’s why it’s so important to know resistance training is very much positive for general health in its own right.

But surely resistance and aerobic training have distinct benefits, right?

That’s true, yes.

But in general this applies more to fitness-type benefits.

Things like:

Increased aerobic fitness (or VO2max) and mitochondrial adaptations with aerobic training
Or increased muscle mass and strength or power with resistance training

Even with these adaptations, there’s more crossover than many realise.

For example:

Resistance training can improve aerobic fitness and mitochondrial function
And aerobic training can improve strength and muscle mass

Sure, these benefits are not as great as with the opposing exercise mode.

But it’s not an “all-or-nothing” scenario.

Instead, the adaptations to aerobic and resistance training are very much on a continuum:

So - what’s this all mean for the “best” type of exercise for general health?

The most effective exercise is the one you will actually do.

Full stop.

Nothing matters more than sticking to exercise - whatever that might be.

So it’s really up to you to find what you enjoy - and can stick to - the most.

This begs the question:

Is it easier to stick to aerobic or resistance training?

We know participation in resistance training is lower than aerobic training.

But in an interesting paradox, clinical studies often show better adherence and lower dropout with resistance training compared to aerobic training.

It’s interesting to reflect on why this might be:

Is it because resistance training often has more immediate effects on fitness (such as strength gains), which may serve as positive feedback?
Or, perhaps the often greater opportunities for social interaction between researchers and participants (for example, during rest periods) resistance training studies keeps people engaged for longer?

Either could be possible.

But the reality is the exercise you’re more likely to stick to is the one YOU enjoy the most.

Contrary to common belief, the health benefits of resistance and aerobic training are more similar than different.

Both forms of exercise have benefits. And the combination gives us even more benefit.

So, do both if you can.

But doing either is a whole lot better than nothing.

As always, thanks for being here.

See you next Saturday,

Jackson

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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.