Should I take a pre-workout supplement — are they safe?

Most pre-workout supplements contain caffeine (150–350 mg), beta-alanine, citrulline, and various proprietary ingredients, the evidence-supported components are caffeine (Solid (1) for acute performance enhancement) and citrulline malate (Promising (2) for blood pressure response during exercise and potential exercise capacity effects), but several pre-workout formulations contain stimulants beyond caffeine (synephrine, DMAA, yohimbine at high doses) that carry cardiovascular risk, particularly in men with undiagnosed hypertension or arrhythmia predisposition (Jeukendrup & Gleeson, Sports Nutrition, 2019).

The FDA has issued warnings on specific pre-workout ingredients. DMAA (dimethylamylamine) has been linked to cardiac events, stroke, and deaths. Yohimbine at high doses can precipitate arrhythmias in susceptible individuals. The category is poorly regulated, proprietary blend labels do not require full disclosure of doses. Men over 40 with any cardiovascular risk factors (hypertension, family history, elevated hs-CRP) should avoid pre-workouts with proprietary stimulant blends and stick to products where all ingredients and doses are fully disclosed on the label.

Honesty Scale: Caffeine in pre-workouts, Solid (1) for acute performance. Stimulant blends, Unsupported (5) for safety in cardiovascular-risk men.

What to do: If you want a pre-workout effect, 200 mg of caffeine from coffee or a single-ingredient caffeine capsule, taken 30–45 minutes before training, is safer, cheaper, and as effective as any proprietary blend. Stop before 2 PM to protect sleep.

For the full picture, read The Supplementation Deep Dive