Finding the energy to exercise in the morning or after a long day is a common problem. This might explain why pre-workout supplements have become so popular. These supplements can bring you more focus and energy for your training sessions – making it possible to get to the gym, no matter how tired you are.

Pre-workout supplements usually contain multiple ingredients – each of which have different effects on the body.

The primary ingredient in most pre-workouts are stimulants such as caffeine or guarana (a plant which contains caffeine). Stimulants help increase focus and alertness. Caffeine may also make workouts feel easier.

Research shows even a single dose of pre-workout supplement containing caffeine before exercising can lead to small improvements in the number of repetitions a person can do, their power and the amount of weight they can lift during a session.

However, these benefits may solely be due to the caffeine itself. When pre-workout supplements are directly compared against the same dose of caffeine on its own, the supplements generally don’t outperform caffeine. Sometimes, caffeine even works as well or better in improving performance.

Taking between 3-6mg of caffeine per kg (around 225-450 mg for a 75kg person, the equivalent of 2-4 cups of strong coffee) can increase strength by around 7%. It can also enhance endurance by around 15%. This might not sound like much, but over time this can lead to significant training gains.

Alongside caffeine, pre-workout supplements contain other ingredients that reportedly help reduce fatigue and boost........

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