THE EFFECTS OF YOHIMBINE INGESTION ON PSYCHOPHYSIOLOGICAL RESPONSES TO MAXIMAL EXERCISE AT VARYING TIMES OF DAY
Carson Elwell, Kailey Luiken, Rebecca Rogers, Tyler Williams, Christopher Ballmann, FACSM. Samford University, Birmingham, AL.
Maximal exercise can induce prominent alterations in psychophysiological responses to exercise, many of which may be modulated by time of day. Yohimbine Hydrochloride (YHM) is an alpha-2-adrenergic receptor antagonist popular in many commercially available supplements which increases sympathetic stimulation. Recent evidence has shown YHM increases pain tolerance, motivation, and feelings of energy in humans during exercise which may have implications for improved exercise adherence. However, it is unknown if YHM differentially influences psychophysiological responses to exercise at different times of the day. The purpose of this study was to study the effects of YHM ingestion on psychophysiological responses during maximal rowing exercise at varying times of the day. Physically active females participated in three counterbalanced rowing trials: 1) Morning-Placebo (AM-PL), 2) Morning-Yohimbine (AM-YHM), and 3) Afternoon-Control (PM). For each AM trial, participants consumed their respective treatment 20 minutes before exercise while no treatment was given for PM. Participants then completed a 2000m rowing time trial. Rate of perceived exertion (RPE), energy, fatigue, alertness, and focus was measured throughout. Findings showed that YHM ingestion resulted in greater energy levels (p= 0.003) during morning times compared to PL. However, no other differences between trials existed for RPE (p= 0.217), fatigue (p= 0.501), alertness (p= 0.081), or focus (p> 0.999). Therefore, YHM may be an effective supplemental strategy to improve feelings of energy in the morning but has limited effects on other psychophysiological responses to maximal exercise.
Elwell, C; Luiken, K; Rogers, R; Williams, T; and Ballmann, FACSM, C
"THE EFFECTS OF YOHIMBINE INGESTION ON PSYCHOPHYSIOLOGICAL RESPONSES TO MAXIMAL EXERCISE AT VARYING TIMES OF DAY,"
International Journal of Exercise Science: Conference Proceedings: Vol. 16:
2, Article 38.
Available at: https://digitalcommons.wku.edu/ijesab/vol16/iss2/38