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Purpose: Different aspects of pacing in endurance events have been investigated, however, there are very limited information on pacing strategies during open-water swimming. The aim was to describe and compare the pacing profile used by male and female open-water swimmers (OW-swimmers) during the 5-, 10- and 25 km races in the main international competitions. Methods: A total of 438 performances were analysed for 5 km, 579 for 10 km and 189 for 25 km, from 2012 to 2017. Swimmers were divided into four groups based on finishing time. G1 whose finishing times were within 0.5% of the winner's time, G2 between 0.51% and 1% slower than winner's time; G3 between 1.1% and 2% slower than winner's time; G4 over 2% of winner's time. Kolmogorov-Smirnov test was used to verify the normal distribution of data and repeated measures ANOVA was performed. Results: G1 adopted a negative pacing and significantly increased the speed in the last split compared with the other groups during the 5-, 10- and 25-km races in both males and females (p < .001). During the 5- and 10-km race, the last split speed of G1 was significantly faster compared to the other groups in both males and females (p < .05). Conclusions: OW-swimmers that used a conservative approach remaining in G1 until the finish of the race, increase the possibility to win a medal in the main international competitions. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to assess 16-wk improvements of physical fitness, metabolic, and psychological parameters in people living with HIV (PLWH) exercising with the support of a smartphone application, as compared with a control group exercising without application. Methods: This was a randomized, open-label, pilot study enrolling PLWH in a 16-wk protocol consisting of moderate physical activity three times per week, which included an initial coach-supervised period of 4 wk, followed by 12 wk where participants trained independently. Participants were allocated to either an experimental group that trained using a smartphone application (APP) or a control group that practiced following a hard copy training program (No-APP). At baseline (BL) and after 16 wk (W16), patients were assessed for cardiorespiratory fitness, body composition, blood lipid profile, and POMS. Results: Forty-eight PLWH were screened and 38 were eligible: 20 were allocated to the APP group and 18 to the No-APP group. Two APP and two No-APP participants were lost to follow-up. Intention-to-treat analysis showed a W16 improvement from BL of ≥15% V˙ O2peak in 13 (72%) of 18 in APP, but only in 3 (19%) of 16 in No-APP participants (P = 0.025). Significant W16 improvements were observed in APP, but not in No-APP participants, in V˙O2peak; fat mass and fat-free mass percent; total cholesterol, LDL cholesterol, and triglycerides; vigor; and total mood by POMS. Accordingly, significant percent change differences between the APP and the No-APP groups were observed in V˙O2peak; fat and fat-free mass percent; total cholesterol, LDL cholesterol, and triglycerides; and depression, vigor, anger, and total mood by POMS. Conclusions: Exercising using a smartphone application improved cardiorespiratory fitness, body composition, cholesterol profiles, and psychological outcomes in PLWH. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate whether the change in (sub)maximal heart rate after intensified training is associated with the change in performance. Thirty subjects were recruited who performed cardiopulmonary exercise tests to exhaustion 2 weeks before (pre), 1 week after (post) and 5 weeks after (follow-up) an 8-day non-competitive amateur cycling event (TFL). The exercise volume during the TFL was 7.7 fold the volume during the preparation period. Heart rate and cardiopulmonary parameters were obtained at standardised absolute submaximal workloads (low, medium and high intensity) and at peak level each test. Subjects were classified as functionally overreached (FOR) or acute fatigued (AF) based on the change in performance. No differences between FOR and AF were observed for heart rate (P =.51). On total group level (AF + FOR), post-TFL heart rate decreased significantly at low (−4.4 beats·min−1, 95% CI [−8.7, −0.1]) and medium (−5.5 beats·min−1 [−8.5, −2.4]), but not at high intensity. Peak heart rate decreased −3.4 beats·min−1 [−6.1, −0.7]. O2pulse was on average 0.49 ml O2·beat−1 [0.09, 0.89] higher at all intensities after intensified training. No changes in ⩒O2 (P =.44) or the ventilatory threshold (P =.21) were observed. Pearson's correlation coefficients revealed negative associations between heart rate and O2pulse at low (r = −.56, P <.01) and medium intensity (r = −.54, P <.01), but not with ⩒O2 or any other submaximal parameter. (Sub)maximal heart rate decreased after the TFL. However, this decrease is unrelated to the change in performance. Therefore, heart rate seems inadequate to prescribe and monitor intensified training. [ABSTRACT FROM AUTHOR]

Exercise is known to have beneficial effects on cognitive function. This effect is greatly favored by an exercise-induced increase in neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), especially with high-intensity exercises (HIE). As a complication of type 1 diabetes (T1D), a cognitive decline may occur, mostly ascribed to hypoglycaemia and chronic hyperglycaemia. Therefore, the purpose of this study was to examine the effects of acute HIE on cognitive function and neurotrophins in T1D and matched controls. Ten trained T1D (8 males, 2 females) participants and their matched (by age, sex, fitness level) controls were evaluated on 2 occasions after familiarization: a maximal test to exhaustion and an HIE bout (10 intervals of 60 s at 90% of their maximal wattage followed by 60 s at 50 W). Cognitive tests and analyses of serum BDNF, IGF-1, and free insulin were performed before and after HIE and following 30 min of recovery. At baseline, cognitive performance was better in the controls compared with the T1D participants ( p < 0.05). After exercise, no significant differences in cognitive performance were detected. BDNF levels were significantly higher and IGF-1 levels were significantly lower in T1D compared with the control group ( p < 0.05) at all time points. Exercise increased BDNF and IGF-1 levels in a comparable percentage in both groups ( p < 0.05). In conclusion, although resting levels of serum BDNF and IGF-1 were altered by T1D, comparable increasing effects on BDNF and IGF-1 in T1D and healthy participants were found. Therefore, regularly repeating acute HIE could be a promising strategy for brain health in T1D. [ABSTRACT FROM AUTHOR]

The article discusses research conducted to investigate the variations of physiological and perceptual variables during a 10,000-meter race walking event in an effort to trace a performance profile of the distance. Researchers evaluated 14 male athletes. They found that they spent 95.4% at 90-100% of their peak heart rate and that during the race, a shift toward higher heart rate values was observed because the percentage of heart rate increased by 3.6% in the last 1,000-meter sector.