Once upon a time, cardio was king. 

Running was what got us fit, slim, healthy. 

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And then people started getting knee problems. People who’d run for years found that their cartilage had been ground into fine flour. Women who’d spent years in stepper classes started complaining of Baker’s Cysts. Achilles’ tendons snapped, shin splints dogged aching legs and gradually the fitness industry started to look for an alternative.

HIIT took over as a more effective form of fat burning, low impact exercise – lasting only 30 minutes and putting way less stress on the joints.

And then PTs and influencers found that it was really the weight-lifting element of these sessions that gave us that all-too-enviable shape. 

It was old fashioned lifting that really sculpted arms, got us bubble butts, defined abs.

Running – that cheap, easy-to-get-better-at, glorious outdoor activity was pushed to the sidelines in favour of Body Pump sessions, weights rooms, kettle bell classes.

Of course, some people have lifted their entire lives – balancing lifting with football, rugby, swimming. They’ve used it as a means to improve strength, to improve their abs and glutes for sports and movement.

But there are others – and especially trainers – who are now insisting that weight lifting is all you need to do to be fit.

When I told a PT the other day that I was going to resume my running schedule to start warming up for a half marathon in October, he looked horrified.

‘You’ll never get the physique you’re after if you keep running,’ he told me.

And as any runner will tell you, that couldn’t be further from the point.

That’s the problem with weight lifting culture, in my experience. 

Weight lifting is amazing and is probably the single best thing you could do as a long distance runner in protecting yourself from injury. 

Yet the community around weight lifting is almost exclusively concerned with aesthetics. 

It’s about how your regime makes you look, not how you feel. It’s about lifting the most amount for the smallest number of reps – so you can then look at your weight card and feel great. 

Running (and other cardio sports) on the other hand, are about how genuinely fit and agile you are. 

Footballers spend hours in strength and conditioning sessions…but many also do yoga, ballet, core.

A weight lifter might be able to do a 250kg squat six times. A runner might be able to run 60km. Now, that runner might not be able to lift the same amount but they should certainly be lifting something by way of strength and conditioning. But they probably do have some upper body strength, simply by virtue that they’re always moving.

It seems highly unlikely, however, that these walking meatballs in the weights room who grunt after every two reps would be able to run a marathon.

They aren’t always cardiovascularly fit – and isn’t that the thing that we all want to be? Isn’t that what stops us from having heart attacks and what not? Sure, you sweat and you get out of breath when you’re lifting but hardly to the same extent. 

Aside from the physical aspect, cardio – in my experience and many other’s – is a mental relief. 

When we run, it gives us the space to think – or not to think. You can allow yourself to be entirely consumed by your playlist or actually process thoughts as you move along. 

The Runner’s High isn’t a myth – keep going long enough and you’ll reach a point where you’re grinning like a goon for no apparent reason. There’s nothing like it.

In a weights room, however, you release a tonne of cortisol and testosterone which in my experience, means leaving feeling shattered and grumpy. There’s no ‘walking on a cloud’ sensation afterwards. 

That’s not to say that that weight lifting doesn’t offer moments of clarity. For some, the concentration of specific muscle groups and being really in tune with how each individual part is working is almost yogic.

‘Weight lifting for me is like meditation and a mental relief,’ Ella, 26, tells Metro.co.uk.

‘When I do yoga my head switches off from the outside world and I solely focus on how my body feels, connecting mind, body and breath.

‘I focus on even weight distribution and technique so that I don’t do any damage. I switch on every muscle and pay close attention to how everything feels – you can’t ignore your body when lifting heavy or you’ll do yourself an injury.

‘I keep my headphones on at all times so that I don’t have to listen to grunts and if I don’t fancy chatting to people in the gym, they won’t bother me. And, of course, my music really psychs me up when I need it for that extra push.’

So let’s be clear, we should be doing both weights and cardio.

Lifting without cardio doesn’t make sense. Cario without weights is a one-way street to injury. Doing a few weight sessions a week undeniably helps you on the spin bike or on the road. You feel like you’ve got a battery pack on your back giving you an extra lift.

But weights alone encourages people to merely be concerned with how they look, how ripped they are. 

Just take a look at the different attitudes towards food.

Weight lifting falls into two categories – shredding or bulking.

Either you’re trying to cut fat and calories so you can get down to a 10% body fat (which is where you can start seeing a six pack emerging), or you’re doubling your calorie intake so that you can get big and build muscle on top. Either way, it’s an aesthetic-led diet.

Runners, on the other hand, carb-load for two days before a big event and otherwise seem to have a pretty laissez-faire attitude towards food.

How much body fat do you actually need?

You need a certain amount of fat to remain healthy and alive. For many of us who weight train, we’re trying to get our bodies to start using our excess fat resources as fuel – creating muscle and cutting padding for an overall sculpted look.

But cut too much and you start to eat away at your ‘essential’ fat – the stuff that keeps our bodies moving.

For men, that’s anything under 6% and women under 10%. You need those minimums to maintain basic physical and mental health.

According to Built Lean, these are the percentages that you’re probably looking at, according to your lifestyle:

Athletes

Men 6-13%, women 14-20%

Fitness 

Men 14-17%, women 21-24%

Average

Men 18-24%, women 25-31%

Obese

Men 25% +, women 32% +

They may burn it off on the road…or they may not. But the point is how far your body can take you, what your body can do – not what it looks like.

While many weight lifters will claim the same – that it’s about how much the body can lift, how strong the body is, there is an undeniable stress on what shape the body is in.

And that just can’t be healthy.

Variation, after all, is the spice of life.

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