International guidelines suggest limiting sodium intake to 86–100 mmol/day, but average intake exceeds 150 mmol/day. Participants in physical activities are, however, advised to increase sodium intake before, during and after exercise to ensure euhydration, replace sodium lost in sweat, speed rehydration and maintain performance. A similar range of health benefits is attributable to exercise and to reduction in sodium intake, including reductions in blood pressure (BP) and the increase of BP with age, reduced risk of stroke and other cardiovascular diseases, and reduced risk of osteoporosis and dementia. Sweat typically contains 40–60 mmol/L of sodium, leading to approximately 20–90 mmol of sodium lost in one exercise session with sweat rates of 0.5–1.5 L/h. Reductions in sodium intake of 20–90 mmol/day have been associated with substantial health benefits. Homeostatic systems reduce sweat sodium as low as 3–10 mmol/L to prevent excessive sodium loss. “Salty sweaters” may be individuals with high sodium intake who perpetuate their “salty sweat” condition by continual replacement of sodium excreted in sweat. Studies of prolonged high intensity exercise in hot environments suggest that sodium supplementation is not necessary to prevent hyponatremia during exercise lasting up to 6 hr. We examine the novel hypothesis that sodium excreted in sweat during physical activity offsets a significant fraction of excess dietary sodium, and hence may contribute part of the health benefits of exercise. Replacing sodium lost in sweat during exercise may improve physical performance, but may attenuate the long-term health benefits of exercise.
Martin J. Turner and Alberto P. Avolio
Stacy D. Hunter, Mandeep S. Dhindsa, Emily Cunningham, Takashi Tarumi, Mohammed Alkatan, Nantinee Nualnim and Hirofumi Tanaka
Obesity is associated with arterial stiffening and diminished quality of life. Bikram yoga may be a feasible alternative to traditional exercise among obese individuals. Accordingly, the purpose of this study was to investigate the impact of Bikram yoga, a heated style of hatha yoga, on arterial stiffness in normal and overweight/obese adults.
Forty-three (23 normal body mass index or BMI; 20 overweight/obese) apparently healthy participants completed an 8-week Bikram yoga intervention. Body composition was estimated via dual energy x-ray absorptiometry, arterial stiffness was measured via brachialankle pulse wave velocity, and health-related quality of life was assessed via RAND 36-Item Short Form survey at baseline and at the end of the 8-week intervention.
After the intervention, brachial-ankle pulse wave velocity decreased (P < .05) in overweight/obese participants while no such changes were observed in normal BMI participants. In the quality of life measures, emotional well-being improved (P < .05) in both groups, and general health improved (P < .05) only in the normal weight BMI group.
Bikram yoga ameliorates arterial stiffness in overweight/obese adults and can positively impact quality of life regardless of BMI.
Oscar Mac Ananey, Brendan McLoughlin, Ann Leonard, Lewena Maher, Peter Gaffney, Gerard Boran and Vincent Maher
Several obesity related factors are reported to exacerbate premature arterial stiffening, including inactivity and metabolic disarray. The aim of the current study was to investigate the relationship between physical activity, arterial stiffness and adiposity using objective methods. To further explore the role of adiposity in this complex process, obesity associated anthropometric and humoral biomarkers were measured.
Seventy-nine healthy, lifelong nonsmoking subjects were recruited. Habitual physical activity was measured using accelerometry. Arterial stiffness [augmentation index (AIx) and pulse wave velocity (PWV)] was measured using tonometry. Body composition was estimated using bioimpedence. Adipose associated biomarkers, leptin and adiponectin, were also measured.
Sedentary time was significantly associated with AIx (r = 0.38, P < .001), PWV (r = 0.33, P < .01), body fat composition (r = 0.40, P < .001) and age (r = 0.30, P < .01). Moderate-to-vigorous physical activity (MVPA) was inversely correlated with AIx (r = –0.28, P < .05), body fat composition (r = –0.30, P < .01), postprandial insulin (r = –0.35, P < .01), and leptin/adiponectin ratio (r = –0.28, P < .05). MVPA, body fat composition, and postprandial insulin remained independent predictors of AIx but not PWV.
The more time healthy individuals spend being sedentary, the greater their body fat and arterial stiffness. Conversely higher activity levels are associated with reduced body fat and less arterial stiffness.
Saowaluck Suntraluck, Hirofumi Tanaka and Daroonwan Suksom
diabetes mellitus is characterized by hyperglycemia due to insulin resistance, which over time leads to a myriad of micro- and macrovascular complications ( Caballero et al., 1999 ), including endothelial dysfunction and arterial stiffening ( Sena, Pereira, & Seica, 2013 ). Land-based exercise training has
Andrew O. Agbaje, Eero A. Haapala, Niina Lintu, Anna Viitasalo, Juuso Väistö, Sohaib Khan, Aapo Veijalainen, Tuomo Tompuri, Tomi Laitinen and Timo A. Lakka
stiffness in adolescents . Eur J Appl Physiol . 2018 ; 118 ( 11 ): 2367 – 76 . PubMed ID: 30099609 doi:10.1007/s00421-018-3963-3 30099609 10.1007/s00421-018-3963-3 19. Hudson LD , Rapala A , Khan T , Williams B , Viner RM . Evidence for contemporary arterial stiffening in obese children
Guohua Zheng, Xin Zheng, Junzhe Li, Tingjin Duan, Kun Ling, Jing Tao and Lidian Chen
.1038/jcbfm.2009.188 10.1038/jcbfm.2009.188 Rucka , D. , Marek , J. , Rucklova , Z. , Lubanda , J.C. , Korinek , J. , & Linhart , A. ( 2015 ). Arterial stiffening contributes to impairment of cerebrovascular reactivity in patients with coronary artery disease without carotid stenosis