This study examined the effects of Ramadan on cycling repeated-sprint ability (RSA) and corresponding diurnal variations.
Twelve active men performed an RSA test (5 × 6-s maximal sprints interspersed with 24 s passive recovery) during morning and afternoon sessions 1 wk before Ramadan (BR), during the second (R2) and the fourth (R4) weeks of Ramadan, and 2 wk after Ramadan (AR). Maximal voluntary contraction was assessed before (MVCpre), immediately after (MVCpost), and 5 min after the RSA test (MVCpost5). Moreover, hematocrit, hemoglobin, and plasma sodium and potassium (K+) concentrations were measured at rest and after the RSA test and MVCpost.
Overall, peak power (Ppeak) during the RSA test decreased throughout the 5 sprints. Ppeak measured in the first sprint and MVCpre were lower during Ramadan than BR in the afternoon (P < .05) and higher in the afternoon than the morning BR and AR (P < .05). However, this diurnal rhythmicity was not found for the last 4 sprints’ Ppeak, MVCpost, and MVCpost5 in all testing periods. Furthermore, the last 4 sprints’ Ppeak, MVCpost, MVCpost5, and morning MVCpre were not affected by Ramadan. [K+] measured at rest and after the RSA test and MVCpost were higher during Ramadan than BR in the afternoon (P < .05) and higher in the afternoon than the morning during Ramadan (P < .05).
Fatigability is higher in the afternoon during Ramadan, and, therefore, training and competition should be scheduled at the time of day when physical performance is less affected.
Aloui is with the High Inst of Sport and Physical Education, University of Sfax, Sfax, Tunisia. Chaouachi, Chtourou, and Haddad are with the Research Laboratory “Sport Performance Optimization,” National Center of Medicine and Sciences in Sport, Tunis, Tunisia. Wong is with the Technological and Higher Education Institute of Hong Kong, Hong Kong. Chamari is with the Research and Education Center, Aspetar, Qatar Orthopedic and Sports Medicine Hospital, Aspire Zone, Doha, Qatar. Souissi is with ISSEP Ksar-Saïd, Manouba University, Manouba, Tunisia.