Circadian Changes in Urinary Bicarbonate, Nitric Oxide Metabolites and pH in Female Player during Handball Camp Involved in an Exercise, Rest and Sleep Cycle.

Abstract

Bicarbonate and nitric oxide levels are important humoral factors in the blood and are affected by the human body's physical condition. There are few reports, however, on changes in blood bicarbonate and nitric oxide levels during exercise and rest. Since urinary bicarbonate and nitric oxide metabolites reflect the levels of bicarbonate and nitric oxide in the blood, we studied circadian changes in 6 female athletes by monitoring their urinary pH and their levels of urinary bicarbonate and nitric oxide metabolites. Measurements were taken during exercise, rest and sleep. Six female athletes participated in a 3-day team handball training camp where they followed a schedule of exercise, rest and sleep. Urinary samples were collected immediately before and after handball training, at bed-time and upon waking. The urinary pH and levels of urinary bicarbonate and nitric oxide metabolites, including nitrite and nitrate, were examined with a blood gas analyzer and a NOx analyzer. The samples collected after handball training, as compared to the samples taken before exercise, showed a decreased pH, a decrease in levels of bicarbonate and little change in NO metabolites. During rest, urinary bicarbonate, NO metabolites and pH increased markedly in all 6 subjects. The levels of urinary bicarbonate, NO metabolites and pH significantly decreased upon waking. This study took into account the subjects' various physiological conditions when considering the significance of their changes in urinary bicarbonate, NO metabolites and pH during the 3 day handball training program. There were significant circadian changes in the urinary pH, and in the levels of urinary bicarbonate and nitric oxide metabolites, in the athletes involved in the exercise, rest and sleep program at team handball camp.

Monitoramento do treinamento no judô: comparação entre a intensidade da carga planejada pelo técnico e a intensidade percebida pelo atleta

“…Therefore, this strategy involves training sessions performed at high intensity with in comparison to the ones regularly carried out (15) . However, it has been reported that long periods of high intensity activities during the training camps can cause noticeable physiological disorders in the athletes (16,17) , such as eating behavior disorders, severe muscle damage and dehydration/electrolytes loss (18,19) . Thus, Fry et al (20) state the importance of suitable training loads periodization, with sufficient recovery periods in order to avoid undesired adaptations.…”

Morning and evening exercise

“…Several studies have recently confirmed the presence of time-of-day effects of exercise on these variables 34, 35. Therefore, health and disease outcomes in response to exercise may depend on the time of day the exercise is performed 36, 37. Hobson et al 38 suggest the existence of a time-of-day effect on aerobic exercise for improving aerobic exercise capacity.…”

Significance of Post-Exercise Increment of Urinary Bicarbonate and pH in Subjects Loaded with Submaximal Cycling Exercise

“…Marked increase of urinary bicarbonate and pH means that the blood pH will become acidified by leftover hydrogen ion in the blood. This blood acidification may correlate with fatigue after heavy exercise (Moriguchi et al 2002b). In spite of these facts, there are few reports on the changes in urinary HCO3 − during and after systemic exercise because urinary HCO3 − has usually been considered negligible, and urinary pH is around 5.5 (Pitts et al 1949).…”