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Forget Caffeine Supplements For Exercise, Coffee Will Do?

Do I need to stop drinking coffee to get the most exercise performance impact out of my caffeine supplements?

This is a common question. People think they need to stop having coffee to make themselves more sensitive to the effects. But is this true? Lets find out…

But before we do, you might be thinking, hang on, I’ve got IBS so is it ok for me to have coffee or caffeine?

So here I’m going to cover IBS and…

  1. How much caffeine is in your regular brew?
  2. How you might benefit from using caffeine?
  3. What are the risks you need to know about using caffeine?
  4. How To Use Caffeine
  5. Do You Need To Stop Drinking Coffee To Get The Most Performance Benefit?
  6. Take-away Messages

1. How Much Caffeine Is In Coffee (…and other stuff)?

Do you know how much caffeine is in your regular brew? Take a little look at this:

You’ll notice I put painkillers in the chart – some products contain caffeine to help improve the effects of the painkiller.

2. What Are The Benefits Of Using Caffeine?

There’s been loads of research into the benefits of caffeine (1,2,3,24), but there’s still a lot more to find out (4), such as a greater understanding around anxiety and performance. Pre-event and competitions can get us a bit nervous or anxious.

Like I used to get a bit anxious before fitness tests when I was in the Army, because I wanted to smash my previous performances (- by the way, I was in the 300 club, which means I scored the highest for the press-ups, sit-ups and run tests). And I’d also try to beat as many other people as possible too! Best effort all the way!! And competitive! And that’s another reason why I’m obsessed with helping my clients succeed.

Feeling anxious or nervous can affect our gut and bring on symptoms, especially if you have IBS. So we need to have a strategy in place to manage these feelings. And know what to feed and fuel ourselves with that won’t aggravate symptoms but aid our performance.

Having an expert in sports nutrition and IBS is key here.

Since excessive caffeine can increase the feelings of anxiety (5), having this before your event/competition could further increase your anxiety levels, which could then have a detrimental effect on your performance… and consequently defeating the object of taking it in the first place! So you need to stay within the limits. Know your tolerances. And follow your plan.

Research has shown caffeine can be beneficial for:

  • Reducing your perception of fatigue – allowing you to work harder! (5)
    • And the benefit of caffeine seems to be particularly beneficial when you’re fatigued in the mid/later stages of exercise
  • Improving endurance performance (1,6,7), such as running, cycling, cross country skiing (24) and Ironman (9). The 2021 ISSN Position Stand on Caffeine suggests aerobic endurance exercise has the most consistent and greatest level of benefit from caffeine use (24). Caffeine also benefits endurance performance in the heat and at altitude (24), which would be of benefit to military personnel 
  • Improving anaerobic exercise (6,7,8,12), such as resistance exercise – muscular strength and endurance (1,10,11, 24), sprints (12) and cycling time trials (11)
  • Lifting mood and alertness (10,13,15) – hence soldiers use it on Exercises, Tours and Ops for increased attention, vigilance and reaction times, especially when you’re sleep deprived. And I know this from personal experience from being in the army
  • Cognitive performance (24) – alertness, concentration, complex reaction time, problem-solving and reasoning

3. What Are The Risks Of Taking Caffeine?

Taking more than 6mg per kilogram of body weight increases the risks of side effects such as nausea, anxiety, irritability (21), “jittery”, sleep problems (6,22), increased heart rate (13,20,) and gut issues (7).

Up to 400mg per day isn’t associated with any health risks in healthy adults (22). But having too much caffeine can be harmful (10,13). Death from caffeine appears to be rare (20), but there has been reports in the media over the years.

As I’ve mentioned above, if you’re prone to feeling anxious whether it’s before a competition or not, then you may not want to take caffeine, especially as this could compromise your overall performance.  

Research has shown genetic variation with how caffeine is absorbed, metabolised and used in the body (24, 25). Which can then impact on the level of benefit, and it’s affect on sleep and anxiety. So it’s wise to test and adjust your caffeine intake to identify your personal benefit and any negative effects (and do it during training rather than saving it for an event/competition where you might get caught out).

If you choose to use caffeine supplements, you can help minimise your risks of buying contaminated or fake supplements which could cause you harm, by using Informed Sport certified products.

*Just as an important point to note, having more than 200mg caffeine a day whilst your wife or partner is pregnant – about 2 cups of instant coffee, increases risk of miscarriage and low birthweight (19,20).

N.B. If you suffer with IBS, then you may need to limit or avoid the amount of caffeine and caffeinated products you use. Because it can bring on symptoms in some people. UK clinical guidelines for IBS recommend limiting tea and coffee to a max. of 3 cups per day (26). I’ve had numerous patients and clients who have had issues with caffeine so we’ve had to make some adjustments.  Find out what to do about your IBS here.

4. How To Use Caffeine?

  • Current evidence-based guidelines state 3-6mg per kilogram body weight (total dose) (5,6,9,24)
  • No greater improvement with more than 9mg per kilogram body weight
    • And the risks of side effects increase with over 6mg per kilo body weight (13) and excess can be fatal (24)
  • You can take caffeine in coffee, energy drinks, pre-workout supplements, energy gels, tablets, chewing gum, candy, mouth rinses, aerosols, amongst many other forms of caffeinated products (24)
    • Different sources of caffeine absorb at different rates (24) so you may want to experiment
  • Follow product guidelines for when to take, but usually it’s 30-60 minutes before exercise (6,15,17) although current research suggests this depends on the source of caffeine, for example chewing gum Vs a tablet (24)
  • Can be taken during endurance exercise to give you a boost (11)
    • Note how much caffeine you have so you don’t accidentally overdose (20)

5. Do You Need To Stop Drinking Coffee?

Do you need to stop drinking coffee and stop having other caffeinated products for a certain period of time in order to get the most benefit from caffeine?

It seems more research is required because there’s lots of conflicting results and study limitations (24).

But I would say the simple answer is likely no (9,16). Although it’s a bit more complex than that.

Response can vary between people and there can be a dose-dependent effect (1,13). So not everyone is going to get the same impact with the same dose. 

And “more isn’t more” (- see my points above).

And there may be a prolonged effect in non-users (15).

There are some studies and reports that have said you need to stop drinking coffee and having other caffeinated products to get the most benefit so you can improve your sensitivity to caffeine’s effects.

But some people can get horrible caffeine withdrawal effects which could compromise training in the lead up to taking caffeine. Which would end up being counterproductive!

Then other sources say you don’t need to refrain from caffeine to enhance benefits. Or, there’s no difference in results between people who regularly consume caffeine compared to those that don’t (9,15,21).

So my simple answer is no, you don’t need to stop having caffeine to get the most benefit when you do then supplement, but it will be a matter of trial and error and monitoring the effects. And any gut issues.

By the way, if you do decide to try caffeine withdrawal to see if you benefit from it’s reintroduction, then I’d recommend doing it gradually. Especially if you usually have shedloads of brews every day, because, for example, if you usually have about 6 brews a day and then just stop, then you’re likely to get withdrawal symptoms like headaches and irritability.


6. Take-Away Messages

  1. Beneficial for increasing alertness, mood, endurance and high intensity exercise and reduces perception of effort or pain
  2. If you regularly drink coffee, you don’t need to stop this, to get the most out of using it for your exercise performance (9,16)
  3. Coffee will do! – You don’t have to buy caffeine supplements to get a performance benefit, but different caffeinated products have different benefits, like some absorb quicker from one type of product compared to another and some are easier or more practical to take during exercise, so it’s a matter of weighing up the pros and cons of different products, such as chugging down a brew Vs chewing some gum before/during exercise. And the ideal timing can vary depending on the product
  4. Guidelines suggest using 3-6mg per Kilogram of bodyweight (total dose)
  5. Take 30-60mins before exercise (but commonly 60 minutes before exercise although this depends on the product and source of caffeine)
  6. No benefit of taking 9mg or more of caffeine – “more is not more”! And exceeding the dose could be harmful. In the least, you’ll get side effects
  7. Caffeine can compromise your sleep!
  8. It’s best to get the basics right first, getting your diet right first before dabbling with supplements or sports foods. “Food First” approach. Then do a ‘needs assessment’ of whether or not you would benefit from supplements 👍

The level of potential benefit from caffeine can vary depending on things like your genetics and the source of the caffeine, and if you’ve got IBS or not, so I’d recommend you test and adjust. But importantly, invest in the help of an expert to guide and support you.

P.S. Drinking coffee doesn’t dehydrate you (15,18). More info about fluids and hydration here. 

And there’s more info about supplements here.

I hope you found this useful and interesting. But you need a bespoke plan to get the most benefit! And it’s more beneficial to have your diet dialled in – get the basics right first before dabbling with supplements and performance aids.

And when you’ve got IBS, sports supplements and sports foods can affect your symptoms, so you need to know what you’re doing to maximise performance and recovery without aggravating your IBS. And that’s where I come in.

It’s crucial to get your food and fluid intake right if you want to control your IBS symptoms, and if you want train harder, go faster and recover quicker from training sessions and competitions. Dietary requirements are highly individualised and there’s no ‘one size fits all’ approach. Working with a Registered Clinical & Sports Dietitian to develop a bespoke plan based on your unique requirements will help to ensure the most appropriate strategy and best results are achieved.

The information, including but not limited to, text, graphics, images and other material contained on this website are for informational purposes only. No material on this site is intended to be a substitute for professional medical advice, examination, diagnosis, or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new treatment or health care regimen, or before making any changes to your existing treatment, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.


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