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Objectives: Use of objectively measured physical activity (PA) in older adults to assess relationship between PA and risk of all-causes mortality is scarce. This study evaluated the associations of PA based on accelerometry and a questionnaire with the risk of mortality among older adults from a city in Southern Brazil., Design: A cohort study., Setting: Urban area of Pelotas, Southern Brazil., Participants: A representative sample of older adults (≥60 y) from Pelotas, enrolled in 2014., Measurements: Overall physical activity (mg), light physical activity (LPA), and moderate to vigorous physical activity (MVPA) were estimated by raw accelerometer data. The International Physical Activity Questionnaire estimated leisure time and commuting PA. Hazard ratios (excluding deaths in the first 6 mo) stratified by sex were estimated by Cox regression analysis considering adjustment for confounders., Results: From the 1451 older adults interviewed in 2014, 145 died (10%) after a follow-up of an average 2.6 years. Men and women in the highest tertile of overall PA had on average a 77% and 92% lower risk of mortality than their less active counterparts (95% confidence interval [CI] = .06-.84 and 95% CI = .01-.65, respectively). The highest tertile of LPA was also related to a lower risk of mortality in individuals of both sexes (74% and 91% lower risk among men and women, respectively). MVPA statistically reduced the risk of mortality only among women (hazard ratio [HR] = .30 and HR = .07 in the second and third tertiles). Self-reported leisure-time PA was statistically associated with a lower risk of mortality only among men. Women in the highest tertiles of commuting PA showed a lower risk of mortality than those in the reference group., Conclusion: Accelerometry-based PA was associated with a lower risk of mortality among Brazilian older adults. Older individuals should practice any type of PA. J Am Geriatr Soc 68:137-146, 2019., (© 2019 The American Geriatrics Society.)

The aim of the study was to compare the maximal physiological responses during three protocols: maximal test on land cycle ergometer, maximal test on water cycling in an indoor pool at 27 °C (WC27) and at 31 °C (WC31). Moreover, the submaximal physiological responses were compared according cycling cadences and water temperatures during the water protocols. Ten young men were included and performed the protocols in separate days. Blood lactate (BL) concentration, heart rate (HR), oxygen uptake (VO2), ventilation (VE) and thermal comfort (TC) were collected during the exercise. The maximal HR and VO2 showed no significant differences between the protocols: HRmax: 189 ± 7 (Land), 188 ± 14 (WC27), 185 ± 9 bpm (WC31) and VO2max: 4.2 ± 0.4 (Land), 4.1 ± 0.5 (WC27) and 4.3 ± 0.5 l min(-1) (WC31). However, the maximal BL demonstrated significant lower values during the water protocols compared to the land protocol (p=0.018). All the submaximal physiological responses showed significant differences between the cadences (60, 70, 80 and 90 rpm). The effect of water temperature was significant for TC response (p=0.001) showing higher values at 31 °C than 27 °C (TCW27: 7 ± 1 and TCW31:9 ± 1). In conclusion, higher physiological responses were showed by increasing the cadence by 10 rpm and the subjects were more comfortable when cycling in the lower water temperature.

Increased body temperature is thought to be an important component of the higher perception of exertion that is a feature of fatigue during exercise in the heat but a causal relationship has yet to be demonstrated. We have investigated the effect of passive heating on the perception of exertion during a standard bout of exercise and also assessed the effect of cooling the head on compensating for the increased body temperature on the feelings of exertion. Ten male subjects performed a 14-min cycling exercise [average power approximately 63% of maximum power output ( W(max))] at an ambient temperature of 35 degrees C at resting rectal temperature [mean (SD): 37.49 (0.27) degrees C; control (CON) trial] on one occasion, and after sitting in a sauna to raise rectal temperature [mean (SD): 38.95(0.13) degrees C; sauna (SAU) trial]. During the exercise, subjects reported their ratings of overall perceived exertion (RPE), perceived exertion of the legs (RPE(legs)) and thermal comfort (TC). A blood sample was collected by the end of the exercise for determination of plasma glucose, lactate and prolactin and haematocrit. RPE values were significantly elevated after passive heating [mean (SE): 14.5 (0.7) units in CON and 17.2 (0.5) units in SAU, at the end of exercise; P<0.001] as were the RPE(legs) ( P<0.01), while ratings of TC were similar in CON and SAU trials. Passive heating increased blood glucose ( P<0.05) but had no effect on lactate at the end of the exercise. Plasma prolactin was markedly elevated as a result of the sauna exposure [mean (SE): 1598 (152) versus 225 (31) mU l(-1) in SAU and CON trials, respectively; P<0.001]. Six of the subjects repeated the two trials but with the face cooled during exercise (trials CON(FAN) and SAU(FAN)) that was achieved by combining face fanning and spraying the face with a mist of cooled water. Face cooling decreased RPE values after sauna to a point that no differences between the two conditions existed. RPE(legs) scores and heart rate, however, remained higher in SAU(FAN) compared with CON(FAN) ( P<0.05). We conclude that hyperthermia is a causative element of the increased perception of exertion during submaximal exercise in the heat and that the effect of increased core temperature on the feelings of exertion is modulated by face cooling.