Dose-Response Effects of Short-Term Rhodiola rosea Supplementation on Cognitive Function and Readiness to Perform in Athletes: A Randomized, Crossover, Double-Blind, and Placebo-Controlled Study
Authors: Koozehchian Majid , Newton Andrew , Mabrey Gina , Naderi Alireza 
Published: May 2024

Background: Rhodiola rosea (RR) is renowned for its adaptogenic qualities across diverse cultures. Contemporary research delves deeper into its potential neuroprotective capabilities and role in augmenting cognitive functions. Given the imperative nature of peak cognitive performance in athletes, the influence of RR supplementation has emerged as a focal point of scientific inquiry. This study elucidates the dose-response relationship of short-term RR consumption on cognitive prowess in resistance-trained athletes. Methods: Twenty-seven resistance-trained athletes (13 males, 14 females; 22±3 y; 170.4±10.7 cm; 75.4±21.9 kg) completed a baseline (BL) and three distinct conditions in random order: low-dose RR (LD: 200 mg/d of RR combined with 1.3 g/d of maltodextrin), high-dose RR (HD: 1.5 g/d of RR), and a placebo (PL: 1.5 g/d of maltodextrin). Each supplementation phase lasted 7d, separated by a 7-day washout period before commencing the subsequent condition. After the supplementation, participants undertook a Stroop color-word test and completed a readiness to perform using a visual analog scale. Data were analyzed using a two-way (within-within) analysis of variance (p≤0.05) with LSD's post hoc when appropriate. RESULTS: Participants were assessed using the Stroop Word-Color test at BL and following each treatment phase. In the Word section, there was a significant improvement. Post hoc analysis revealed that both RR doses surpassed BL and PL results. The scores were as follows: BL [107.8±10.6 counts (c)], PL (118.4±11.7 c), LD (122.0±15.1 c), and HD (125.2±16.2 c; p<0.001). Participants completed tasks more swiftly in the Color section after taking both RR doses than at BL. The results were: BL (79.3±12.3 c), PL (85.3±10.6 c), LD (88.0±11.1 c), and HD (91±24.8 c; p<0.031). In the Word-Color section, both RR doses led to significant cognitive enhancements, with scores being BL (94.0±18.5 c), PL (104.3±16.2 c), LD (108.9±20.6 c), and HD (113.0±18.3 c; p<0.001). When all domains were summed, a notable enhancement was observed. Subsequent post hoc analysis indicated that both RR dosages exceeded the scores of BL and PL. The respective scores were: BL (281.1±31.1 c), PL (307.9±29.7 c), LD (318.9±36.5 c), and HD (329.6±47.8 c; p<0.001). No significant alterations were noted in readiness (p>0.05). CONCLUSION: This study underscores RR as a potential cognitive enhancer for athletes. Both the low and high doses of RR yielded significant benefits in the Stroop Word-Color test, suggesting a dose-responsive relationship. However, RR did not influence the athletes' sense of readiness. While the findings are promising, further research is essential to determine RR's comprehensive effects and ideal dosing.

The researchers personally financed this study, bearing all costs. Such a method guarantees the research's autonomy, free from potential influences that might come with external financial support or grants.

This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.