Fitness

When to Take Pre-Workout

How long before a workout to take your pre-workout, why caffeine sets the timing, how long it lasts, and why evening workouts need a different plan.

Updated · 3 min read

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Timing is everything. Leave the house five minutes earlier and you might have snagged the last vegan maple donut. Change the clocks by one hour for daylight saving and we're all thrown into crisis mode. (Why am I so hungry? It's only 10 a.m.!)

So if timing is everything, it matters for your pre-workout too. As the name suggests, you take it before working out. But how much before? Here's how to time it.

Why does caffeine decide when to take pre-workout?

Let's be honest: one of the main reasons people use a pre-workout is the caffeine. It's also the ingredient with the strongest evidence. The International Society of Sports Nutrition concludes that caffeine improves many kinds of exercise performance at 3 to 6 mg per kilogram of body weight, so it's largely the caffeine that determines your timing.

Caffeine is rapidly and completely absorbed from your gut and quickly reaches every tissue in your body, but it takes a little while to build up to its full effect.

How long before a workout should you take pre-workout?

In caffeine research, the most common timing is 60 minutes before exercise, and many pre-workout labels, including ours, suggest about 30 minutes. A good rule of thumb is 30 to 60 minutes before you start. That way the caffeine is kicking in as you finish your warm-up and get into the main part of your session.

Some practical tips:

  • Drink it on the way. Mix it before you leave home or as you change in the locker room.
  • Experiment. Everyone absorbs and responds to caffeine a little differently, so try both ends of the window and notice what feels best.
  • Start small. If you're new to pre-workout, begin with half a serving.

Forgot to take it early? No sweat (save that for the stair climber). You'll still get the benefit; it may just arrive partway through your workout.

How long does a pre-workout last?

Caffeine doesn't wear off as fast as it kicks in. Its half-life, the time it takes your body to clear half of it, ranges from about 2.5 to 10 hours depending on genetics, age, medications, pregnancy and other factors. A larger dose also leaves more caffeine in your system for longer. For a deeper look, read how long pre-workout lasts.

Is it bad to take pre-workout in the evening?

It can be. In a sleep study, a large dose of caffeine taken even six hours before bed noticeably disrupted sleep. If you train in the evening, consider a lower-caffeine option, a smaller serving or none at all. We recommend enjoying our pre-workouts in the morning or early afternoon.

Keep an eye on your total intake too. The FDA cites 400 mg a day from all sources as an amount not generally associated with negative effects for most healthy adults. If you're pregnant, sensitive to caffeine or have a heart condition, talk to your doctor first.

What else in a pre-workout makes timing less critical?

Caffeine isn't the only reason to take a pre-workout. If you've chosen well, yours should also include nitrate-rich vegetables to support blood flow, electrolytes for hydration, and adaptogens to help your body handle the stress of training. Renewable Energy combines 90mg of caffeine from organic green coffee bean, matcha and yerba mate with ashwagandha, rhodiola, ginseng and maca, beetroot and pomegranate juice powders, and coconut water. Take one scoop about 30 minutes before your workout.

New to pre-workouts? Start with what a pre-workout supplement is.

Frequently asked questions

How long before a workout should I take pre-workout?

About 30 to 60 minutes before. Caffeine studies most often use 60 minutes, and many labels, including Ora's, suggest about 30 minutes.

Can I take pre-workout right before exercising?

You can, but the caffeine may not reach its full effect until partway through your session. Taking it a little earlier works better for most people.

Can I take pre-workout at night?

It may affect your sleep. A large dose of caffeine taken six hours before bed disrupted sleep in one study, so choose a lower-caffeine option or skip it for late workouts.

How long does pre-workout stay in your system?

Caffeine's half-life ranges from about 2.5 to 10 hours, so some of it can stay in your system well into the evening.

References

  1. Guest NS, et al. International society of sports nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr. 2021;18(1):1. https://pubmed.ncbi.nlm.nih.gov/33388079/
  2. Magkos F, et al. Caffeine use in sports, pharmacokinetics in man, and cellular mechanisms of action. Crit Rev Food Sci Nutr. 2005;45(7-8):535-62. https://pubmed.ncbi.nlm.nih.gov/16371327/
  3. Drake C, et al. Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. J Clin Sleep Med. 2013;9(11):1195-200. https://pubmed.ncbi.nlm.nih.gov/24235903/
  4. US Food and Drug Administration. Spilling the beans: how much caffeine is too much? Consumer update, content current as of August 2024. https://www.fda.gov/consumers/consumer-updates/spilling-beans-how-much-caffeine-too-much