Five Days of Tart Cherry Supplementation Improves Exercise Performance in Normobaric Hypoxia.

Previous studies have shown tart cherry (TC) to improve exercise performance in normoxia. The effect of TC on hypoxic exercise performance is unknown. This study investigated the effects of 5 days of tart cherry (TC) or placebo (PL) supplementation on hypoxic exercise performance.

Hypoxic-induced resting ventilatory and circulatory responses under multistep hypoxia is related to decline in peak aerobic capacity in hypoxia.

Background: Several factors have been shown to contribute to hypoxic-induced declined in aerobic capacity. In the present study, we investigated the effects of resting hypoxic ventilatory and cardiac responses (HVR and HCR) on hypoxic-induced declines in peak oxygen uptake ([Formula: see text]O).

Methods: Peak oxygen uptakes was measured in normobaric normoxia (room air) and hypoxia (14.

Influence of Step Frequency on the Dynamic Characteristics of Ventilation and Gas Exchange During Sinusoidal Walking in humans.

We tested the hypothesis that restricting either step frequency (SF) or stride length (SL) causes a decrease in ventilatory response with limited breath frequency during sinusoidal walking. In this study, 13 healthy male and female volunteers (mean ± SD; age: 21.5 ± 1.

Economical and preferred walking speed using body weight support apparatus with a spring-like characteristics.

Background: A specific walking speed minimizing the U-shaped relationship between energy cost of transport per unit distance (CoT) and speed is called economical speed (ES). To investigate the effects of reduced body weight on the ES, we installed a body weight support (BWS) apparatus with a spring-like characteristics. We also examined whether the 'calculated' ES was equivalent to the 'preferred' walking speed (PWS) with 30% BWS.

Dietary nitrate supplementation effect on dynamic cerebral autoregulation in normoxia and acute hypoxia.

We tested the hypothesis that increasing the nitric oxide (NO) bioavailability by dietary nitrate would recover the hypoxia-induced reduction in dynamic cerebral autoregulation (CA). Twelve healthy males (age 21 ± 2 years) completed four days of dietary supplementation with a placebo or inorganic nitrate drink (140-ml beetroot juice per day) followed by 60-min of normoxia or hypoxia (fraction of inspired oxygen [FiO] = 13%). Duplex ultrasonography was used to perform volumetric change-based assessment of dynamic CA in the internal carotid artery (ICA).

Relationship Between Cerebral Oxygenation and Skin Blood Flow at the Frontal Lobe during Progressive Hypoxia: Impact of Acute Hypotension.

We investigated the relationship between cerebral oxygenation (COX) and skin blood flow (SkBF) at the left frontal lobes of 10 healthy young men during progressive hypoxia (∼ -1 h at each of 21%, 18%, 15%, and 12% of inspired oxygen [FiO]). Acute hypotension was manipulated by a thigh-cuff-release technique, where a pressure of 220 mmHg was applied at both thigh muscles for 3 min and the cuff was immediately released to induce acute hypotension. While the resting baseline for COX before the thigh-cuff release manipulation decreased gradually with the reduction of FiO (P < 0.

Why do we transition from walking to running? Energy cost and lower leg muscle activity before and after gait transition under body weight support.

Background: Minimization of the energetic cost of transport (CoT) has been suggested for the walk-run transition in human locomotion. More recent literature argues that lower leg muscle activities are the potential triggers of the walk-run transition. We examined both metabolic and muscular aspects for explaining walk-run transition under body weight support (BWS; supported 30% of body weight) and normal walking (NW), because the BWS can reduce both leg muscle activity and metabolic rate.

Prevalence of Falls on Mount Fuji and Associated with Risk Factors: A Questionnaire Survey Study.

Since little is known about the detailed situations of falls on Mount Fuji, the aim of this study was to clarify the risk factors of falls on Mount Fuji in Japan. We conducted a questionnaire survey of 556 participants who had climbed Mount Fuji and collected the following information: fall situation, mental status, fatigue feeling, sex, age, climbing experience on Mount Fuji and other mountains, summit success, whether staying at a lodge, use of a tour guide, and symptoms of acute mountain sickness. Among the 556 participants, 167 had a fall (30%).

Sex differences in respiratory and circulatory cost during hypoxic walking: potential impact on oxygen saturation.

Energy expenditure (EE) during treadmill walking under normal conditions (normobaric normoxia, 21% O) and moderate hypoxia (13% O) was measured. Ten healthy young men and ten healthy young women walked on a level (0°) gradient a range of speeds (0.67-1.

Absence of cardiovascular drift during prolonged arm-crank exercise in individuals with spinal cord injury.

Study Design: Observational study OBJECTIVE: To investigate the effects of prolonged arm-crank exercise on cardiovascular drift (CV) in spinal cord injury (SCI).

Setting: This is a community-based supervision study METHODS: Ten participants with motor -complete or incomplete SCI (lesion level T7-L1), and 10 able-bodied (AB) participants matched for age performed a 40-min arm-crank exercise at an intensity of 50% of peak oxygen uptake (VO).

Results: During the exercise, there were no significant differences between the groups in VO, tissue O saturation in the biceps brachii (active muscle), and chest and arm skin temperature (all P > 0.

Impact of Dietary Nitrate Supplementation on Executive Function During Hypoxic Exercise.

We investigated the effects of 4-day dietary beetroot (BR) juice supplementation on executive function assessed by color-word Stroop task (CWST) in hypoxia (fraction of inspired oxygen [FiO] = 0.1395). Eight healthy young men performed 25-minute leg cycling exercise (target heart rate, 140 bpm) randomly with placebo (PL) juice or BR supplementation.

Combined effects of exposure to hypoxia and cool on walking economy and muscle oxygenation profiles at tibialis anterior.

We investigated combined effects of ambient temperature (23°C or 13°C) and fraction of inspired oxygen (21%O or 13%O) on energy cost of walking (: J·kg·km) and economical speed (ES). Eighteen healthy young adults (11 males, seven females) walked at seven speeds from 0.67 to 1.

Jump training with blood flow restriction has no effect on jump performance.

This study investigated whether jump training with blood flow restriction (BFR) improves jump performance compared to jump training without BFR under similar exercise intensity in healthy young humans. The participants were twenty healthy males who were assigned to either jump training with BFR (n = 10) or jump training without BFR [control (CON); n = 10] groups. All subjects completed five sets of 10 repetitions with one-minute intervals of half-squat jumps (SJ) at maximal effort, four days a week for four weeks.

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

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 % FiO).

Impact of Wearing Graduated Compression Stockings on Psychological and Physiological Responses during Prolonged Sitting.

We investigated the impact of wearing vs. not wearing graduated compression stockings on psychological and physiological responses in 18 healthy young people (12 men and six women) during 3 h prolonged sitting. Profiled of Mood States (POMS) scores did not show marked differences between with and without stockings.

Impact of ambient temperature on energy cost and economical speed during level walking in healthy young males.

We measured oxygen consumption and carbon dioxide output during walking [per unit distance () values] for 14 healthy young human males at seven speeds from 0.67 to 1.67 m s (4 min per stage) in thermoneutral (23°C), cool (13°C), and hot (33°C) environments.

Energy cost and lower leg muscle activities during erect bipedal locomotion under hyperoxia.

Background: Energy cost of transport per unit distance (CoT) against speed shows U-shaped fashion in walking and linear fashion in running, indicating that there exists a specific walking speed minimizing the CoT, being defined as economical speed (ES). Another specific gait speed is the intersection speed between both fashions, being called energetically optimal transition speed (EOTS). We measured the ES, EOTS, and muscle activities during walking and running at the EOTS under hyperoxia (40% fraction of inspired oxygen) on the level and uphill gradients (+ 5%).

Impact of Sleeping Altitude on Symptoms of Acute Mountain Sickness on Mt. Fuji.

Unlabelled: Horiuchi, Masahiro, Tadashi Uno, Junko Endo, Yoko Handa, and Tatsuya Hasegawa. Impact of sleeping altitude on symptoms of acute mountain sickness on Mt. Fuji.

Barometric pressure change and heart rate response during sleeping at ~ 3000 m altitude.

We investigated effects of change in barometric pressure (P ) with climate change on heart rate (HR) during sleep at 3000 m altitude. Nineteen healthy adults (15 males and four females; mean age 32 years) participated in this study. We measured P (barometry) and HR (electrocardiography) every minute during their overnight stay in a mountain lodge at ~ 3000 m.

Muscle oxygenation profiles between active and inactive muscles with nitrate supplementation under hypoxic exercise.

Whether dietary nitrate supplementation improves exercise performance or not is still controversial. While redistribution of sufficient oxygen from inactive to active muscles is essential for optimal exercise performance, no study investigated the effects of nitrate supplementation on muscle oxygenation profiles between active and inactive muscles. Nine healthy males performed 25 min of submaximal (heart rate ~140 bpm; EX) and incremental cycling (EX) until exhaustion under three conditions: (A) normoxia without drink; (B) hypoxia (FiO= 13.

Management Effectiveness of a Secondary Coniferous Forest for Landscape Appreciation and Psychological Restoration.

We investigated the influence of forest management on landscape appreciation and psychological restoration in on-site settings by exposing respondents to an unmanaged, dense coniferous (crowding) forest and a managed (thinned) coniferous forest; we set the two experimental settings in the forests of the Fuji Iyashinomoroi Woodland Study Center. The respondents were individually exposed to both settings while sitting for 15 min and were required to answer three questionnaires to analyze the psychological restorative effects before and after the experiment (feeling (the Profile of Mood States), affect (the Positive and Negative Affect Schedule), and subjective restorativeness (the Restorative Outcome Scale). To compare landscape appreciation, they were required to answer another two questionnaires only after the experiment, for scene appreciation (the semantic differential scale) and for the restorative properties of each environment (the Perceived Restorativeness Scale).

Measuring the Energy of Ventilation and Circulation during Human Walking using Induced Hypoxia.

Energy expenditure (EE) during walking includes energy costs to move and support the body and for respiration and circulation. We measured EE during walking under three different oxygen concentrations. Eleven healthy, young, male lowlanders walked on a treadmill at seven gait speeds (0.

Effects of Short-Term Acclimatization at the Summit of Mt. Fuji (3776 m) on Sleep Efficacy, Cardiovascular Responses, and Ventilatory Responses.

Horiuchi, Masahiro, Shiro Oda, Tadashi Uno, Junko Endo, Yoko Handa, and Yoshiyuki Fukuoka. Effects of short-term acclimatization at the summit of Mt. Fuji (3776 m) on sleep efficacy, cardiovascular responses, and ventilatory responses.

Muscle activities during walking and running at energetically optimal transition speed under normobaric hypoxia on gradient slopes.

Energy cost of transport per unit distance (CoT; J·kg-1·km-1) displays a U-shaped fashion in walking and a linear fashion in running as a function of gait speed (v; km·h-1). There exists an intersection between U-shaped and linear CoT-v relationships, being termed energetically optimal transition speed (EOTS; km·h-1). Combined effects of gradient and moderate normobaric hypoxia (15.

Arm-Cranking Exercise Training Reduces Plasminogen Activator Inhibitor 1 in People With Spinal Cord Injury.

Objective: To investigate the effects of arm-cranking exercise training on plasminogen activator inhibitor 1 (PAI-1) as a risk factor of deep vein thrombosis, along with general physical parameters such as muscle strength, aerobic capacity, and hemodynamics, in individuals with spinal cord injury (SCI) and control subjects.

Design: Longitudinal study.

Setting: Community-based supervised intervention.