Caffeine consumption prior to a workout has been shown to decrease perceptions of fatigue. A recent study sought out to find if pre-workout caffeine consumption also has positive effects on strength.


There were two primary research questions:

  1. Would caffeine supplementation increase 1RM strength in the pull-down, hack squat, and bench press?
  2. Would caffeine supplementation increase knee extension reps to failure?

The subjects were eight young women, 20-30 years old, with 1-2 years of strength training experience.

The four measurements taken were 1RM strength in the pull-down, hack squat, and bench press, and reps to failure in the knee extension using a drop set. 


  1. In the caffeinated group, hack squat strength, bench press strength and knee extension reps to failure were significantly greater than the placebo group
  2. There was no noticeable difference in pull down strength between groups

Key Takeaways

  1. Caffeine can boost your performance acutely in terms of both 1RM strength and reps to failure.
  2. The effect is much more pronounced for lower body exercises.  Caffeine will probably give you more of a boost for a heavy squat workout than a heavy bench workout.
  3. You need to take a lot of caffeine to maximize the ergogenic effect.  At least 3mg/kg is generally needed for any ergogenic effects, and 6mg/kg – the dosage in this study – generally seems to be the sweet spot.
  4. If you’re naïve to caffeine, start with a lower dose to see how you tolerate it. If you’ve already built up a tolerance, you’ll probably need to stop using caffeine except for the period around your hardest workout or two each week if you want to reap the performance-boosting effects of caffeine.