Move over creatine and protein shakes. A surprising new gym companion may help boost your next workout: dark chocolate.
A new study published in the journal Frontiers of Physiology reveals a link between dark chocolate and improved physical performance. Participants of the study were tasked with smelling either chocolate or plain water during a leg extension workout routine, with those who smelled dark chocolate completing more repetitions.
The 23 male participants regularly engaged in resistance training and completed three lab sessions after fasting for at least 10 hours the night before. During each session—which were separated from the others by four days—each participant was exposed to either 90% dark chocolate, 60% milk chocolate, or water. The study follows research into chocolate’s health benefits, particularly around the flavonoid compound, which some have linked to improved vascular and brain health.
Each participant had to smell the odor prior to beginning his exercise, and was asked to perform leg extensions until he could no longer continue. At various points in the exercise, participants would smell the designated odor again for at least 30 seconds, rating the pleasantness of the odor as well as how satiated they felt.
Sniffing dark chocolate showed more significant effects on athletic performance. At 90% dark chocolate, participants performed 18 more leg extension repetitions, and nine more reps when smelling 60% milk chocolate. The repetitions were compared with those completed during the control session, in which participants smelled plain water.
Additionally, while dark chocolate was shown to relieve the feeling of hunger, milk chocolate was rated as more pleasurable to smell during the study.
While surprising, the study has several limitations, including the small participant pool and the unclear link between olfactory stimulation and physical endurance and athletic performance. Nevertheless, this line of research is a growing field, with researchers also exploring the effects of peppermint and lavender.
“Olfactory stimuli may alter appetite, affective responses, and exercise performance through psychobiological processes,” the study explains. “However, whether odor-induced changes in appetite and pleasantness translate into measurable improvements in resistance exercise performance remains unclear.”