Supplements for CrossFit and mixed-modal athletes

The CrossFit supplement plan

The "do these five" core

Creatine 5 g/day, daily, any time. Single highest-yield supplement; supports strength, power, and recovery between sets of mixed work.
Beta-alanine 3–5 g/day for 4–6 weeks loading, then 2–3 g/day maintenance. Loads muscle carnosine; biggest gains in the metcon energy range (60s–4 min). Split doses to minimise paresthesia (tingling).
Caffeine 3–6 mg/kg 30–60 min pre-WOD. The most reliable acute performance ergogenic in the legal toolkit. Don't dose evening sessions late — sleep is the limiting factor.
Citrulline malate 6–8 g 30–60 min pre-WOD. Helpful for high-rep wall balls, thrusters, pull-ups, burpees — anything where ammonia handling and blood flow matter.
Whey protein post-workout, plus enough total daily protein (1.6–2.2 g/kg). Don't overthink timing; the daily total matters more.

Background recovery layer

Omega-3 EPA+DHA 2 g/day for DOMS reduction and broader cardiovascular/cognitive benefit. Magnesium glycinate 300 mg at night for sleep quality and cramp prevention. Vitamin D3 to a 25-OH-D target of 30–50 ng/mL — especially important for athletes training indoors and in winter. Daily multivitamin if dietary diversity is low (most CrossFit athletes eat well; a multi is optional).

Programming the supplement timing around the WOD

30–60 min pre-WOD: caffeine + citrulline (+ beta-alanine maintenance dose if loading is complete). Post-WOD: whey protein within 60–90 minutes (or with the next meal if it's coming soon). Daily: creatine (any time), omega-3, vitamin D, magnesium. Pre-bed: magnesium glycinate (and casein if total protein is short for the day).

Competition prep

For the Open or a competition: continue normal routine. The week of competition, ensure beta-alanine is fully loaded (started 4+ weeks prior). Consider tart cherry concentrate 30 mL daily for the 4–5 days bracketing competition to reduce DOMS and improve recovery between events. Don't introduce new supplements in competition week. Sleep, hydration, and food are the bigger competition-week levers.

Sleep and food are the bigger levers

CrossFit's volume punishes poor sleep and inadequate eating. 7–9 hours of sleep consistently outperforms any supplement. 1.6–2.2 g/kg protein, 4–6 g/kg carbohydrate on training days, and adequate total calories (relative energy deficiency in sport is real and common in volume-heavy training).