Browsing by Author "Lee JKW"

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    Assessment of Changes in Physiological Markers in Different Body Fluids at Rest and after Exercise
    (MDPI (Basel, Switzerland), 2022-11-05) Jesuthasan A; Ali A; Lee JKW; Rutherfurd-Markwick K
    Physiological and biological markers in different body fluids are used to measure the body's physiological or pathological status. In the field of sports and exercise medicine, the use of these markers has recently become more popular for monitoring an athlete's training response and assessing the immediate or long-term effects of exercise. Although the effect of exercise on different physiological markers using various body fluids is well substantiated, no article has undertaken a review across multiple body fluids such as blood, saliva, urine and sweat. This narrative review aims to assess various physiological markers in blood, urine and saliva, at rest and after exercise and examines physiological marker levels obtained across similar studies, with a focus on the population and study methodology used. Literature searches were conducted using PRISMA guidelines for keywords such as exercise, physical activity, serum, sweat, urine, and biomarkers, resulting in an analysis of 15 studies for this review paper. When comparing the effects of exercise on physiological markers across different body fluids (blood, urine, and saliva), the changes detected were generally in the same direction. However, the extent of the change varied, potentially as a result of the type and duration of exercise, the sample population and subject numbers, fitness levels, and/or dietary intake. In addition, none of the studies used solely female participants; instead, including males only or both male and female subjects together. The results of some physiological markers are sex-dependent. Therefore, to better understand how the levels of these biomarkers change in relation to exercise and performance, the sex of the participants should also be taken into consideration.
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    Sensory Perception of an Oral Rehydration Solution during Exercise in the Heat
    (MDPI (Basel, Switzerland), 23/09/2021) Kitson O; Rutherfurd-Markwick K; Foskett A; Lee JKW; Diako C; Wong M; Ali A
    Prolonged exercise in the heat elicits a number of physiological changes as glycogen stores are low and water and electrolytes are lost through sweat. However, it is unclear whether these changes provoke an increase in liking of saltiness and, therefore, palatability of an oral rehydration solution (ORS). Twenty-seven recreationally active participants (n = 13 males; n = 14 females) completed sensory analysis of an ORS, a traditional sports drink (TS), and a flavored water placebo (PL) at rest and during 60 min (3 × 20-min bouts) of cycling exercise at 70% age-predicted maximum heart rate (HRmax) at 35.3 ± 1.4 °C and 41 ± 6% relative humidity. Before and after every 20 min of exercise, drinks were rated (using 20-mL beverage samples) based on liking of sweetness, liking of saltiness, thirst-quenching ability, and overall liking on a nine-point hedonic scale. Hydration status was assessed by changes in semi-nude body mass, saliva osmolality (SOsm), and saliva total protein concentration (SPC). After 60 min of exercise, participants lost 1.36 ± 0.39% (mean ± SD) of body mass and there were increases in SOsm and SPC. At all time points, liking of sweetness, saltiness, thirst-quenching ability, and overall liking was higher for the TS and PL compared to the ORS (p < 0.05). However, the saltiness liking and thirst-quenching ability of the ORS increased after 60 min of exercise compared to before exercise (p < 0.05). There was also a change in predictors of overall liking with pre-exercise ratings mostly determined by liking of sweetness, saltiness, and thirst-quenching ability (p < 0.001), whereas only liking of saltiness predicted overall liking post-exercise (R2 = 0.751; p < 0.001). There appears to be a hedonic shift during exercise in which the perception of saltiness becomes the most important predictor of overall liking. This finding supports the potential use of an ORS as a valuable means of hydration during the latter stages of prolonged and/or intense exercise in the heat.