Fasted Cardio: Magic or Myth?

Fasted Cardio: Magic or Myth?

Fasted cardio performed first thing in the morning – is it essential?!

There are arguments back and forth, you have the ‘old school’ bodybuilders suggesting it is imperative and they know this via anecdotal evidence. Then we have the newer ‘evidence based’ coaches that throw up studies saying it makes absolutely no difference.

What do I recommend?

So first off I’ll say that – and I’m no expert when it comes to reading literature – the science does suggest there is little to no difference between fed Vs. fasted cardio.

Despite this being the case, I actually do have 90% of my clients perform their cardio fasted. I have a few reasons for this, and they’re all really simple and no real hard science behind them.

1) Sometimes it’s just easier to ‘get sh*t done’. By this I mean if you set your alarm early, get straight up and smash out your cardio.. That’s it. It’s done for the day! There’s no excuses, nothing can ‘crop up’ during the day.

I know some clients have suggested doing evening cardio.. But, often they end up tired, working late, or having to attend a last minute event etc. The problem with this, is depending on personality type, it cascades. Missing one cardio session turns into missing two cardio sessions… and then it’s ‘oh well, the damage is done this week – I’ll get back on it from Monday’.

Whereas, if you get into the mindset of waking up that 20mins earlier and just heading outside and ‘getting it done’ – you really can’t fail! It becomes part of a schedule and actually sets you up for the day. It’s really rare for any of my clients to not come back to me saying they were dreading it, but now enjoy doing it as it gives them some headspace when no one else is around to interrupt them. I’d argue for people leading a particularly busy/stressful life that it’s actually beneficial for them to do it at this time.

2) There’s a combination of supplements that I like touse to promote a fat burning environment (typically Caffeine + L-Tyrosine or Caffeine + Yohimbine HCL).

These combinations appear to work best when fasted. When we first wake, cortisol (stress hormone) should be relatively high. By taking caffeine, we amplify it’s affects. Now, most people freak out when we mention cortisol – but, at certain times of day – it can be very beneficial. Especially here, as it helps mobilise fatty acids to be used as fuel.

Also, if using Yohimbine HCL it is advised to keep it away from carbohydrate as high levels of insulin seem to cancel out it’s effectiveness. What better time of day do we have low insulin levels naturally? First thing in the morning.

So, if using these two supplements I really think fasted CV is king here.

3) Never settling. Sure theoretically there’s no difference between fasted & fed state cardio. However, you can’t argue with the results 1000’s of shredded bodybuilders have got over the years!

Whenever I do cardio myself, I always start with fasted CV and it hasn’t failed me yet.

I’m one of those people where if something may give me a 2-3% edge – I’ll do it! Why wouldn’t I? If I’m busting ass with training and diet, to me it makes sense to try and maximise EVERYTHING.

If performing the CV fasted is easy to fit into my schedule and may possibly yield a stronger result.. You can be sure I’m going to do it!

I will caveat all of this with a case of it is person dependent after-all. If I have someone that has very poor sleep habits and struggles to get a solid 6-8 hours sleep then I would consider holding fire on fasted cardio.

Likewise, if someone’s schedule really doesn’t allow for it and they can only fit it in say late evening or post workout, we’d go with that option.

Although the ‘big picture’ is just getting your allotted cardio in within a 24 period, I would still prioritise timings like this:

Most preferred = first thing in the morning

Next best option = last thing at night, in between your final meal and bed

Next best option = post workout

Next best option = whenever the hell you can

The bottom line is this; just doing the cardio full stop is what will dictate results, I’d rather them do it whenever suits them than not at all. But, if their schedule allows and if they feel good and don’t mind doing it, to me it makes sense to maximise every effort we can!

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Akash Vaghela is the Founder of RNT Fitness, where his mission is to see a world where everyone experiences the power of a physical body transformation to act as a vehicle for the greater good in their lives. Akash has produced 200+ blogs, 100+ videos and hosts the RNT Fitness Radio podcast, which has amassed over 110,000 downloads in 90+ countries across 100+ episodes. Alongside this, he's been seen in Men's Health, BBC, T-Nation, Elite FTS and the PTDC, while also regularly speaking nationally and internationally on all things transformation.