Pre-workout supplements that promise extra energy and improved exercise performance may be interfering with sleep among teenagers and young adults. A new study suggests that users of these products are more than twice as likely to report extremely short sleep, likely because many of the supplements contain high levels of caffeine and other stimulants.
The findings come from a new analysis of the Canadian Study of Adolescent Behaviors, which explored the use of popular pre-workout dietary supplements such as Bang!, Jack3D, and C4.
Researchers analysed data from more than participants aged between 16 and 30. According to the results, those who said they had used pre-workout supplements during the previous year were more than twice as likely to report sleeping five hours or less per night compared with people who had not used them. Experts generally recommend around eight hours of sleep per night for people in this age group.
“Pre-workout supplements, which often contain high levels of caffeine and stimulant-like ingredients, have become increasingly popular among teenagers and young adults seeking to improve exercise performance and boost energy,” says lead author Kyle T. Ganson, assistant professor at the Factor-Inwentash Faculty of Social Work at the University of Toronto.
“However, the study’s findings point to potential risks to the well-being of young people who use these supplements.”
High caffeine content may affect sleep
Health recommendations suggest adolescents should sleep between eight and ten hours each night, while young adults should aim for seven to nine hours. Despite this, many young people in Canada do not reach these targets.
Researchers say stimulant ingredients found in many pre-workout products could be contributing to sleep problems during a period of life when physical and mental development is still ongoing.
“These products commonly contain large doses of caffeine, anywhere between 90 to over 350 mg of caffeine, more than a can of Coke, which has roughly 35 mg, and a cup of coffee with about 100 mg,” said Ganson.
“Our results suggest that pre-workout use may contribute to inadequate sleep, which is critical for healthy development, mental well-being, and academic functioning.”
Experts suggest more awareness and guidance
The research team says healthcare and mental health professionals — including pediatricians, family physicians and social workers — should discuss the use of pre-workout supplements with young people.
They also advise simple harm-reduction steps, such as avoiding these products 12 to 14 hours before bedtime.
The study’s findings also add to ongoing calls for stronger oversight of dietary supplements in Canada.
“Young people often view pre-workout supplements as harmless fitness products,” Ganson noted.
“But these findings underscore the importance of educating them and their families about how these supplements can disrupt sleep and potentially affect overall health.”
SOURCE
University of Toronto. “Popular pre-workout supplements linked to dangerous sleep loss.” ScienceDaily. ScienceDaily, 9 March 2026. <www.sciencedaily.com/releases/2026/03/260308201618.htm>.
