Physiological Indices of Dehydration in Commercial Motorcycle Riders Operating in Extreme Heat in Maiduguri, North East Nigeria

Background: Commercial motorcycle riders, locally referred to as okada operators, work prolonged hours in outdoor environments without access to adequate hydration facilities. In Maiduguri, where ambient temperatures routinely exceed 40 degrees Celsius, cumulative fluid loss during daily operations poses significant physiological risk. Dehydration impairs cognitive function, reaction time, and cardiovascular efficiency, directly threatening rider and passenger safety. Objectives: This study aims to assess physiological dehydration indices, including urine specific gravity, serum osmolality, and subjective thirst perception, among commercial motorcycle riders in Maiduguri and to quantify daily fluid intake versus estimated fluid loss. Methods: Eighty commercial riders will be recruited from three major areas in Maiduguri. Pre-shift and post-shift urine samples will be collected for specific gravity analysis. Body weight will be measured at both time points to estimate sweat loss. A structured questionnaire will document daily fluid intake and thirst awareness. Descriptive statistics and paired t-tests will be employed. Expected Outcomes: Post-shift urine specific gravity values are expected to exceed the clinically significant dehydration threshold in the majority of participants, with fluid intake significantly below estimated losses. Conclusion: Results will guide public health interventions targeting hydration awareness among informal transport workers in arid North East Nigeria. Keywords: dehydration, heat stress, motorcycle riders, urine specific gravity, Maiduguri.