Beer and Exercise

A randomized controlled trial by de Moraes Pontes et al. (2022) asked whether drinking a beer after an exercise session would influence the recovery trajectory of the participants’ heart rate variability as control of the heart rate shifts from the sympathetic nervous system back to the parasympathetic resting state.  The authors cite quite a few articles to establish the relevance of their question. One is a study by Spaak et al. (2010) where two glasses of red wine or ethanol were found to decrease heart rate variability of resting subjects.  Another (Gomes et al., 2018) described the normal trajectory of heart rate variability during recovery following exercise.  And Benjamin et al. (2021) did a randomized controlled trial where beetroot extract improved heart rate variability both during exercise and during recovery after exercise. 

 

I noticed that de Moraes Pontes et al. (2022) mention that they were not aware of many studies looking at the effect of beer on heart rate recovery after exercise.  I did a quick search and found one randomized controlled trial (Santana et al., 2022) that concluded beer did not affect heart rate variability after exercise.  Considering this was the opposite conclusion, it seems there is room for more research on this topic, specifically whether it is better to drink water rather than beer after exercising.  A meta-analysis of randomized controlled trials would be the best study design for this type of question, but I was unable to find one on beer, exercise, and heart rate variability.  These two randomized controlled trials are a good start in that direction. 

 

The de Moraes Pontes et al. (2022) study presented a flow chart in the format of the Consolidated standards of reporting trials (CONSORT), stating that their report followed those guidelines.  Here you can see that their exclusion criteria were reasonable, and all those not excluded went on to be included in the final analysis.  They do not state how they recruited the participants, and it does not sound like there was any attempt at blinding, but the crossover design would have helped to make sure that the characteristics of the participants drinking beer were similar to those drinking water.  It would be interesting to see if the software they used to measure heart rate variability had been validated against more objective biomarkers. 

 

Looking at the protocol that they registered (https://ensaiosclinicos.gov.br/rg/RBR-2j5294), I notice that they had planned for a 72 hour washout; in the trial this was reduced to 48-72 hours.  They had planned for 25 women and 25 men; however they note that their sample size calculation indicated 11 per group, and they had 15 men and 17 women.  The protocol called for 350 ml of beer or water and they used 300 ml.  The protocol stated that they expected to find the sympathetic nervous system remaining engaged during recovery for the participants who drank beer.  They found this to be true for men but not for women.  The article has a detailed statistics section describing how they analyzed the data.  They note similarity within the groups for age, weight, height, and BMI.  They used Cohen’s d to determine effect size, and they note the large effect sizes found throughout the results.  They note the limitations of their study population; since they were all young (18 to 26 years old), were accustomed to having only 1-2 drinks per week, and did not have any existing heart conditions, these results should not be generalized to other populations.  The authors stated that no conflicts of interest exist.  I did not find any information about the funding for this study. 

 

Overall I felt that this study had a lot of strengths in its design, and provides an interesting angle to look at the effects of alcohol consumption, but I would like to see more studies both asking the same question and also looking at other aspects of physiology to get a more complete picture of what happens to a person when they drink a beer. 

 

References:

 

Benjamim, C. J. R., S. Júnior, F. W., de Figueirêdo, M. Í. L. S., Benjamim, C. J. R., Cavalcante, T. C. F., da Silva, A. A. M., Monteiro, L. R. L., Santana, M. D. R., Garner, D. M., & Valenti, V. E. (2021). Beetroot ( ) Extract Acutely Improves Heart Rate Variability Recovery Following Strength Exercise: A Randomized, Double-Blind, Placebo-Controlled Crossover Trial-Pilot Study. Journal of the American College of Nutrition, 40(4), 307–316. 

 

de Moraes Pontes, Y. M., Benjamim, C. J. R., Augusto Liberalino, G., Porto, A. A., Garner, D. M., & Valenti, V. E. (2022). The effects of acute beer ingestion on recovery of nonlinear heart rate variability after exercise: a randomized, crossover and controlled trial. / Os efeitos da ingestão aguda de cerveja na recuperação da variabilidade não linear da frequência cardíaca após o exercício: um teste randomizado, crossover e controlado. Revista Brasileira de Nutrição e Esportiva, 16(100), 383–395. 

 

Gomes, R. L., Vanderlei, L. C., Garner, D. M., Santana, M. D., de Abreu, L. C., & Valenti, V. E. (2018). Poincaré plot analysis of ultra-short-term heart rate variability during recovery from exercise in physically active men. Journal of Sports Medicine & Physical Fitness, 58(7/8), 998–1005.

 

Santana, M. R. D., Pontes, Y. M. de M., Benjamim, C. J. R., Rodrigues, G. da S., Liberalino, G. A., Mangueira, L. B., Feitosa, M. E., Leal, J., Akimoto, A., Garner, D. M., & Valenti, V. E. (2022). A Single Dose of Beer after Moderate Aerobic Exercise Did Not Affect the Cardiorespiratory and Autonomic Recovery in Young Men and Women: A Crossover, Randomized and Controlled Trial. International Journal of Environmental Research & Public Health, 19(20), 13330. 

 

Spaak, J., Tomlinson, G., McGowan, C. L., Soleas, G. J., Morris, B. L., Picton, P., Notarius, C. F., & Floras, J. S. (2010). Dose-related effects of red wine and alcohol on heart rate variability. American Journal of Physiology. Heart and Circulatory Physiology, 298(6), H2226–H2231.