Effects of Ramadan observance on repeated cycle ergometer sprinting and associated inflammatory and oxidative stress responses in trained young men

Introduction: The effects of Ramadan observance upon repeated sprints and associated inflammatory and oxidative stress responses are not well known. Indeed, the objective was to assess the impact of fasting on muscle performance and selected oxidative and inflammatory parameters in athletes. Methods: Ten young trained boxers were tested during a control period (C), at the end of the first week (R-1), and during the fourth week of Ramadan observance (R-4). On each occasion, they performed three vertical jumps, 10 x 6 s repeated sprints on a cycle ergometer, followed by three final vertical jumps 1 min after. Surface electrodes measured the EMG activity of the vastus lateralis during jumps performed before and after sprinting. Oxidative stress (malondialdehyde, total antioxidant and catalase), inflammatory markers (C-reactive protein, Interleukin-6 and homocysteine), muscle damage (CPK and LDH) and blood glucose were measured at rest and after completing the exercise protocol. Results: The overall sprint performance was reduced at R-1 compared to C (-6.3 ± 1.2%, p = 0.025), but had recovered by R-4. Jump height decreased after the repeated sprints (p<0.01), without significant changes in EMG parameters. Oxidative stress indices, inflammatory markers, and muscle damage measured after the protocol exercise were unaffected during fasting. Conclusion: The correction of sprint performance may highlight some adaptive responses to fasting. The unchanged of the selected fatigue biomarkers after the repeated sprint protocol suggest that the dietary restriction related to Ramadan is not severe enough to induce significant changes in the metabolism of our trained athletes.