scholarly journals Impact of Resistance Exercise under Hypoxia on Postexercise Hemodynamics in Healthy Young Males

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Masahiro Horiuchi ◽  
Arisa Ni-i-nou ◽  
Mitsuhiro Miyazaki ◽  
Daisuke Ando ◽  
Katsuhiro Koyama

We investigated the effects of resistance exercise under hypoxia on postexercise hemodynamics in eight healthy young males. The subjects belonged to a track & field club (sprinters, hurdlers, and long jumpers) and engage in regular physical training (1-2 h per day, 3-5 days per week). Each participant performed eight sets of bilateral leg squats with a one-minute interval under normoxia (room air) and hypoxia (13 % FiO2). During a 60-minute recovery, we set normoxic condition either after normoxic or hypoxic exercise. These two experimental protocols (normoxia and hypoxia) were performed in a random order with a one-week washout period. The leg squat exercise consists of 50 % 1-RM (14 repetitions) × 5 sets and 50% 1-RM (repetitions max; 7 repetitions) × 3 sets. The resting period between each set was 1 min, and a total of 91 repetitions were performed. Blood pressure, heart rate (HR), and several biomarkers were measured pre- and postexercise. The mean arterial pressure (MAP) significantly decreased after exercise compared to the pre-exercise values under both conditions (P < 0.05). The MAP at 20 and 30 min of recovery in hypoxia was significantly lower than in normoxia (P < 0.05, respectively). The antidiuretic hormone significantly increased after 60 min of recovery in both conditions; moreover, the values in hypoxia were significantly higher than those in normoxia (P < 0.05). The delta changes in MAP from baseline (pre-exercise) were significantly related to changes in HR from baseline in normoxia (r = 0.560, P < 0.001) but not in hypoxia. These results suggest that the hypoxic condition elicits greater hypotension after resistance exercise in comparison to normoxia. Moreover, the underlying mechanisms for the attenuation of hypotension after resistance exercise may differ between normoxia and hypoxia.

1987 ◽  
Vol 57 (01) ◽  
pp. 55-58 ◽  
Author(s):  
J F Martin ◽  
T D Daniel ◽  
E A Trowbridge

SummaryPatients undergoing surgery for coronary artery bypass graft or heart valve replacement had their platelet count and mean volume measured pre-operatively, immediately post-operatively and serially for up to 48 days after the surgical procedure. The mean pre-operative platelet count of 1.95 ± 0.11 × 1011/1 (n = 26) fell significantly to 1.35 ± 0.09 × 1011/1 immediately post-operatively (p <0.001) (n = 22), without a significant alteration in the mean platelet volume. The average platelet count rose to a maximum of 5.07 ± 0.66 × 1011/1 between days 14 and 17 after surgery while the average mean platelet volume fell from preparative and post-operative values of 7.25 ± 0.14 and 7.20 ± 0.14 fl respectively to a minimum of 6.16 ± 0.16 fl by day 20. Seven patients were followed for 32 days or longer after the operation. By this time they had achieved steady state thrombopoiesis and their average platelet count was 2.44 ± 0.33 × 1011/1, significantly higher than the pre-operative value (p <0.05), while their average mean platelet volume was 6.63 ± 0.21 fl, significantly lower than before surgery (p <0.001). The pre-operative values for the platelet volume and counts of these patients were significantly different from a control group of 32 young males, while the chronic post-operative values were not. These long term changes in platelet volume and count may reflect changes in the thrombopoietic control system secondary to the corrective surgery.


2000 ◽  
Vol 25 (1) ◽  
pp. 68-78 ◽  
Author(s):  
Craig S. Ballantyne ◽  
Stuart M. Phillips ◽  
Jay R. Macdonald ◽  
Mark A. Tarnopolsky ◽  
J. Duncan Macdougall

We examined the effects of androstenedione supplementation on the hormonal profile of 10 males and its interaction with resistance exercise. Baseline testosterone, luteinizing hormone, estradiol, and androstenedione concentrations were established by venous sampling at 3 hr intervals over 24 hr. Subjects ingested 200 mg of androstenedione daily for 2 days, with second and third day blood samples. Two weeks later, they ingested androstenedione or a placebo for 2 days, in a double-blind, cross-over design. On day 2, they performed heavy resistance exercise with blood sampled before, after, and 90 min post. The supplement elevated plasma androstenedione 2-3-fold and luteinizing hormone ∼70% but did not alter testosterone concentration. Exercise elevated testosterone, with no difference between conditions. Exercise in the supplemented condition significantly elevated plasma estradiol by ∼83% for 90 min. Androstenedione supplementation, thus, is unlikely to provide male athletes with any anabolic benefit and, with heavy resistance exercise, elevates estrogen. Key Words: testosterone, luteinizing hormone, estradiol, fluid shifts, resistance exercise


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shuang Ding ◽  
Yu Guo ◽  
Xiaoya Chen ◽  
Silin Du ◽  
Yongliang Han ◽  
...  

AbstractThe aim of this study was to investigate the mechanisms underlying demyelination and remyelination with 7.0 T multiparameter magnetic resonance imaging (MRI) in an alternative cuprizone (CPZ) mouse model of multiple sclerosis (MS). Sixty mice were divided into six groups (n = 10, each), and these groups were imaged with 7.0 T multiparameter MRI and treated with an alternative CPZ administration schedule. T2-weighted imaging (T2WI), susceptibility-weighted imaging (SWI), and diffusion tensor imaging (DTI) were used to compare the splenium of the corpus callosum (sCC) among the groups. Prussian blue and Luxol fast blue staining were performed to assess pathology. The correlations of the mean grayscale value (mGSV) of the pathology results and the MRI metrics were analyzed to evaluate the multiparameter MRI results. One-way ANOVA and post hoc comparison showed that the normalized T2WI (T2-nor), fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) values were significantly different among the six groups, while the mean phase (Φ) value of SWI was not significantly different among the groups. Correlation analysis showed that the correlation between the T2-nor and mGSV was higher than that among the other values. The correlations among the FA, RD, MD, and mGSV remained instructive. In conclusion, ultrahigh-field multiparameter MRI can reflect the pathological changes associated with and the underlying mechanisms of demyelination and remyelination in MS after the successful establishment of an acute CPZ-induced model.


2017 ◽  
Vol 58 (1) ◽  
pp. 65-72 ◽  
Author(s):  
Gustavo A. Callegari ◽  
Jefferson S. Novaes ◽  
Gabriel R. Neto ◽  
Ingrid Dias ◽  
Nuno D. Garrido ◽  
...  

AbstractThe aim of this study was to investigate the responses of creatine kinase (CK) and lactate dehydrogenase (LDH) after performing different resistance and aerobic exercise protocols. Twelve recreationally trained men (age, 23.2 ± 5.6 years; body mass, 84.3 ± 9.3 kg; body height, 178.9 ± 4.5 cm; and BMI, 26.3 ± 2.3 kg·m2) volunteered to participate in this study. All subjects were randomly assigned to four experimental protocols (crossover): (a) aerobic training at 60% of VO2max, (b) aerobic training at 80% of VO2max, (c) a resistance exercise (RE) session with a bi-set protocol, and (d) an RE session with a multiple sets protocol. Blood samples were collected before, immediately after and 24 hours following the experimental protocols. After 24 hours, there was a significant increase in CK for the 80% of VO2max protocol vs. the bi-set RE session (p = 0.016). Immediately after the protocols, we observed a significant increase in LDH among certain groups compared to others, as follows: multiple sets RE session vs. 60% of VO2max, bi-set RE session vs. 60% of VO2max, multiple sets RE session vs. 80% of VO2max, and bi-set RE session vs. 80% of VO2max (p = 0.008, p = 0.013; p = 0.002, p = 0.004, respectively). In conclusion, aerobic exercise performed at 80% of VO2max appears to elevate plasma CK levels more than bi-set RE sessions. However, the bi-set and multiple sets RE sessions appeared to trigger greater levels of blood LDH compared to aerobic protocols performed at 60% and 80% of VO2max.


1978 ◽  
Vol 45 (3) ◽  
pp. 345-349 ◽  
Author(s):  
M. J. Stock ◽  
N. G. Norgan ◽  
A. Ferro-Luzzi ◽  
E. Evans

Measurements of metabolic rate and the thermic response (specific dynamic action) of a 400-kcal liquid meal were made in six subjects at rest and during light exercise. The tests were conducted before (LA1) and after (LA2) a 3-wk sojourn (HA1, HA2, HA3) at 3,650 m on the Monte Rosa. Fasting metabolic rate at rest increased inittally and then fell, as did fasting and fed exercising metabolic rates. The fall in metabolic rates, but not the initial increases, can be ascribed to the change in body weight. Resting thermic responses at altitude were only slightly lower than normal, although peak values were significantly depressed at HA2 (P less than 0.05). The mean exercising thermic response was also significantly lower at HA2 (P less than 0.05) but recovered in HA3 and LA2. In the time taken for thermic responses to decrease and recover there were interindividual differences that were best explained by the previous altitude experience of the subjects. The possibility of a cardiovascular shift during hypoxic exercise causing depression of postprandial metabolism is discussed.


2014 ◽  
Vol 20 (1) ◽  
pp. 54-57
Author(s):  
Rodrigo Dias Martins ◽  
Debora Cantergi ◽  
Jefferson Fagundes Loss

The kihapis a technique used in several oriental martial arts. It is a yell used by practitioners with the ex pectation of enhancing the force of a hit. However, the real effect of using the kihapis unknown. Therefore, this study aims to compare the peak of acceleration of the Dolio-chaguikick in taekwondo performed with and without the use of kihap. Twenty two experienced taekwondo practitioners performed 30 kicks each against a punching bag, alternating in random order with and without kihap, while the acceleration of the punching bag was measured. A t-test was used to compare the difference between the mean acceleration in both conditions. Higher values were found with the use of kihap(7.8 ± 2.8 g) than without the use of kihap(7.1 ± 2.4 g), p< 0.01, r= 0.57. The results indicate that kihapenhances the impact of the kick.


1992 ◽  
Vol 20 (6) ◽  
pp. 445-453 ◽  
Author(s):  
A Lassus ◽  
E Eskelinen

A controlled, randomized, double-blind, parallel-group study compared the effects of ViviScal® (a new food supplement incorporating special marine extracts and a silica compound) with those of a fish extract in the treatment of young males with hereditary androgenic alopecia. The pretreatment histological diagnosis was alopecia with a mild to moderate perifollicular inflammation zone. The study consisted of 20 subjects who received two tablets of ViviScal® once daily and 20 who received two tablets of fish extract once daily for 6 months. The mean patient age and mean duration and severity of baldness compared well between the two groups. Most patients had been treated with long-term topical 2% minoxidil for 1 year or more prior to the study. At baseline and after 6 months' treatment, a biopsy was taken for histological examination. A non-vellus hair count was performed at baseline and after 2, 4 and 6 months. In the fish extract treatment group three patients withdrew from the study before the fourth month due to lack of therapeutic effect. After 6 months' treatment, patients receiving ViviScal® showed a mean increase in non-vellus hair of 38% compared with a 2% increase in the fish extract treatment group (P < 0.0001). In the ViviScal® group, 19 (95%) subjects showed both clinical and histological cure, whereas none treated with fish extract showed any clinical or histological difference after 6 months' treatment ( P < 0.0001). In both groups, a minimal decrease in the erythemal index was observed. In conclusion, ViviScal® appears to be the first highly active treatment for androgenic alopecia in young males.


Author(s):  
Taylor J. Kelty ◽  
Xuansong Mao ◽  
Nathan R. Kerr ◽  
Thomas E. Childs ◽  
Gregory N. Ruegsegger ◽  
...  

Neuroinflammation is an early detectable marker of mild cognitive impairment, the transition state between normal cognition and dementia. Resistance-exercise training can attenuate the cognitive decline observed in patients with mild cognitive impairment. However, the underlying mechanisms of resistance training effects are largely unknown. To further elucidate mechanisms of the known cognitive health benefits from resistance-exercise training, we tested if three weeks of resistance-exercise training could ameliorate lipopolysaccharide-induced neuroinflammation. Five-week-old female Wistar rats received intracerebroventricular injections of lipopolysaccharides to induce neuroinflammation and cognitive impairment. Rats then underwent three weeks of progressive ladder climbing to recapitulate resistance-exercise training in humans. Cognition was assessed towards the end of the training period by novelty object recognition testing. Neuroinflammation was measured one and 24-hours after the last resistance-exercise training workout. Resistance-exercise training ameliorated cognitive impairment, diminished lipopolysaccharide-induced neuroinflammatory cytokine expression, and attenuated astrocyte remodeling in the dentate gyrus 24-hours post exercise. Here, we provide evidence that the ladder-climbing model of resistance-exercise training in rats can improve cognition as early as three weeks. Additionally, these data support the hypothesis that resistance exercise can reduce lipopolysaccharide-induced neuroinflammation in the dentate gyrus.


Medicina ◽  
2019 ◽  
Vol 55 (3) ◽  
pp. 77 ◽  
Author(s):  
Takashi Nakagata ◽  
Yosuke Yamada ◽  
Yoichi Hatamoto ◽  
Hisashi Naito

Background and objectives: The purpose of this study was to compare the energy expenditures (EE) of a single sit-to-stand (STS) movements with slow and normal speeds using a multi-stage exercise test. Materials and Methods: Twelve young males, aged 21–27 years (age, 23.0 ± 1.7 years; height, 171.2 ± 6.1 cm; weight, 64.3 ± 5.6 kg), performed repeated 3-s stand-up and 3-s sit-down (slow) or 1-s stand-up and 1-s sit-down (normal) movement on two different days with random order. All the participants completed multi-stage tests at different STS frequencies per minute. The slope and intercept of the linear regression relationship between the EE (kcal/min) and the STS frequency were obtained, and the slope of the regression was quantified as the EE of an STS. Results: The metabolic equivalents (METs) of the STS-slow was 4.5 METs for the frequency of 10 times/min (in total 1 min), and the net EE was 5.00 ± 1.2 kcal/min. The net EE of the STS-slow was 0.37 ± 0.12 kcal, which was significantly greater than that during the STS-normal (0.26 ± 0.06 kcal). The difference between the EEs of the STS-slow and STS-normal was significantly greater in taller and heavier subjects. Conclusions: We concluded that the intensity of STS-slow movement is moderate, and the EE during an STS-slow (0.37 ± 0.12 kcal) is higher than that during an STS-normal (0.26 ± 0.06 kcal). Our study results will help exercise and/or health professionals prescribe physical activity programs using STS movement for healthy young population groups.


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