How Runners Can Use Caffeine for Endurance, Focus & Ultra Performance

Quick Summary

• Ideal dose: 3–6 mg/kg body weight

• Timing: 30–60 minutes pre-run or when fatigue hits

• Best for: Morning runs, mid-race boosts, overnight ultras

• Sources: Coffee, gels, tablets, chews

• Always test in training—never introduce on race day

What Does Caffeine Do for Runners?

Caffeine is a natural stimulant found in coffee beans, tea leaves, and cacao pods. It works by blocking the neurotransmitter adenosine, which normally signals fatigue. By limiting adenosine’s effects, caffeine helps you feel more alert and energised.

Performance Benefits for Runners:

• Delayed fatigue – You can maintain stamina for longer

• Improved focus – Stay sharp with pacing and strategy

• Enhanced performance – Potentially faster, more efficient running

  
  

A review by the International Society of Sports Nutrition (ISSN) confirms that moderate caffeine doses (3–6 mg/kg) improve endurance performance in many athletes. But responses vary — always trial it in training first.

When Should Runners Take Caffeine?

Timing matters. Caffeine peaks in your bloodstream about 30–60 minutes after ingestion.

Common Timing Strategies:

Pre-Run Boost

Ideal for morning or lunchtime runs. Caffeine reduces perceived effort and helps early miles feel easier.

Mid-Race Pick-Me-Up

For longer events like marathons or ultras, caffeine at halfway or during mental dips can be a game changer.

Pre-Dawn Wake-Up Call

Running overnight? A small caffeine boost before sunrise can help you push through sleep deprivation.

How Caffeine Helps Ultrarunners Stay Awake

Ultras involve running through the night, often past 50 or even 100 miles. Caffeine can:

• Maintain alertness during night hours (especially 2–5 a.m.)

• Delay the onset of mental fatigue

• Provide psychological comfort in hard moments

  
  

Large doses can cause jitters or stomach issues. Smaller, regular doses are safer and more sustainable.

Should You Taper Caffeine Before a Race?

Some runners reduce or eliminate caffeine for a few days pre-race to boost sensitivity. The science is mixed, but there’s evidence that even a short 3–7 day break can enhance caffeine’s effects.

Consider This Approach:

• Switch to half-caff or tea during taper week

• Trial the taper during training to see how your body responds

• Don’t go cold turkey if you’re a heavy coffee drinker—it may backfire with headaches and low energy

How Much Caffeine Should Runners Take?

Recommended Dose: 3–6 mg of caffeine per kg of body weight

Instead of one large hit, spread your intake over time:

• 50–100 mg every few hours in ultramarathons

• Adjust based on tolerance and perceived benefit

  
  

Always start low and test in training to avoid side effects like anxiety, GI issues, or rapid heart rate.

Essential Caffeine Tips for Ultrarunning

• Avoid Overuse: Too much caffeine causes restlessness and nausea

• Hydrate Well: Caffeine is mildly diuretic—balance it with water and electrolytes

• Monitor Heart Rate: Especially important in long races under stress

• Fuel Properly: Combine caffeine with carbs, protein, and fat

• Practice in Training: Never try new caffeine strategies on race day

Best Caffeine Sources for Runners

Coffee and Tea

Black Coffee is a staple for many. A typical cup contains 80–100 mg of caffeine.

Green Tea or Black Tea often has slightly lower caffeine levels, plus antioxidants.

Pros: Affordable, widely available.

Cons: Inconsistent dosage; can cause stomach upset if consumed too close to training. Not convenient or always accessible during long ultramarathons.

Energy Gels

Specifically designed for endurance athletes, many gels now offer caffeine.

Pros: Precise dosage; convenient to carry on longer runs or races.

Cons: May be pricey; some runners find the texture challenging to swallow, tastes horrendous!

Try something like SIS Caffeine-Infused Energy Gel, each gel contains 150mg caffeine.

Caffeine Tablets and Chews

Tablets, gummies or caffeinated gum provide a quick, measurable dose.

Pros: Easy to monitor exact intake; portable.

Cons: May lack the additional nutrients (e.g., carbs or electrolytes) found in sports-focused products, hard to chew and sticks to your teeth, tastes horrendous!

Despite the awful taste, I do love to use Caffeine Bullets before workouts and during my overnight ultramarathons.

Coach’s Insight

In overnight ultras, I find smaller, consistent doses of caffeine more effective than one big hit. I usually combine them with a fuelling strategy to avoid energy crashes and GI issues.

Frequently Asked Questions

Is caffeine good for running performance?

Yes, it improves endurance, focus, and reduces perceived effort when used properly.

Can I drink coffee before a race?

Yes, but test it in training first. Coffee is a popular pre-run option.

How much caffeine should I take during a marathon or ultra?

3–6 mg/kg body weight is effective. For ultras, smaller doses (e.g. 100 mg every few hours) work well.

Should I stop drinking coffee before a race?

Some runners benefit from a short caffeine taper. Try it in training to see if it helps you.

Want Help with Race Nutrition?

I offer personalised coaching that includes performance nutrition planning, caffeine timing, and real-world testing advice. Whether you’re racing a 10K or a 100-miler, I’ll help you optimise every detail.

👉 Apply for coaching.

References

International Society of Sports Nutrition (ISSN). (2021). Position stand on caffeine and exercise performance.

European Food Safety Authority (EFSA). (2015). Scientific Opinion on the Safety of Caffeine.

European Journal of Applied Physiology. (2021). Caffeine intake and endurance performance.

Journal of Sports Sciences. (2019). Short-term caffeine withdrawal enhances performance.