The use and dosage of pre-workout supplements amongst recreational athletes

Consumption of pre-workout supplements (PWS) has increased substan- tially in recent years. However, dosages of ingredients vary between man- ufacturers. Therefore, the aim of this study was to analyze ingredients from various products and to survey past and present (4 weeks) consumption behavior. Analysis of ingredients was performed in 30 products according to man- ufacturer’s specifications. Subsequently, online questionnaire was used to assess reasons for taking, timing and dosing of PWS in 39 recreational ath- letes (4 females; 35 males; 25.15 ±3.67 years). Most prevalent ingredients in PWS were caffeine, beta-alanine, L-cit- rulline, L-arginine, L-tyrosine, taurine and creatine. Average dosing per serving were 254 mg caffeine (125–410 mg), 2513 mg beta-alanine (500– 4000 mg), L-citrulline 3506 mg (500–8000 mg), L-arginine 2726 mg (500– 8000 mg), L-tyrosine 1227 mg (150–3000 mg), taurine 1211 mg (90– 2500 mg) and creatine 3031 mg (1000–5000 mg). Average values were in (63%) or below (36%) the recommended ergogenic dosage. Major motives for PWS use were improved concentration, increased blood flow and de- layed onset of fatigue. Most subjects consumed PWS 1–3 times per month. In most cases consumption took place 15–30 min before training. Man- ufacturers’ recommendations for consumption were generally followed. A large number of subjects (82%) reported minor side effects from PWS consumption (e.g. paresthesia, insomnia, headache). Based on current research only caffeine, L-citrulline, L-arginine and tau- rine show relevant direct performance-enhancing effects, while the ben- efit of beta-alanine, L-tyrosine and creatine in PWS seems highly ques- tionable. Dosages of ingredients were safe, but often too low to increase performance.