Study design
POLAND
The study was designed as a double-blind, randomized, placebo-controlled crossover trial. To investigate the effects of BET supplementation, 43 participants were randomly divided into two parallel groups: one (The participants attended four study meetings at the Department of Human Nutrition and Dietetics and the Center of Physical Culture, Poznan University of Life Sciences, Poland. The meetings were conducted before and after each supplementation period. On each study meeting day, participants were invited to two sessions: one in the morning and another in the afternoon. During the morning session, participants had their body composition measured and blood samples were collected in the fasted state. During the afternoon session, participants performed the WAnT and Fight Gone Bad (FGB) tests separated by a twenty-minute break. The participants were familiarized with the testing procedures prior to the beginning of the study. During the familiarization session the participants were instructed about the proper technique of each FGB exercise. There was no need to practice FGB because the participants were already familiar with this workout. Then the participants watched a video of WAnT with a verbal instruction. After adjusting the height of a saddle and imposing external load, the participants practiced WAnT (3 times). All the study meetings for a given participant were performed at the same time of day. The study was conducted from January 2019 to December 2020. All athletes stated that they had not introduced any changes to their lifestyles, training, nutrition, or supplementation during the study.Randomization of the participants was conducted using The study was approved by the local ethical committee (Bioethics Committee at Poznan University of Medical Sciences, Poznan, Poland. Decision no. 1092/17, 9 November 2017) and written informed consent was obtained from all participants before the study began. All procedures were conducted in accordance with the ethical standards of the 1964 Helsinki Declaration. The trial was registered on clinicaltrials.gov (