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Johann Auer, Robert Berent, Markus Prenninger, Thomas Weber, Klaus Kritzinger, Martin Veits, Gudrun Lamm, Elisabeth Lassnig and Bernd Eber

Context:

Effects of a single bout of exercise at moderate altitude on blood pressure (BP) are largely unknown.

Objective:

To evaluate the effect of a single exercise bout at moderate altitude on BP.

Design:

Prospective, observational.

Setting:

Field study, Alpine mountains.

Participants:

127 men, 71 women (138 normotensive, 60 hypertensive).

Intervention:

Exercise duration: 2.5 ± 0.4 h; 650-m difference in altitude.

Main Outcome Measures:

BP and heart rate (HR).

Results:

Hypertensives had (1) higher systolic BP (SBP) and diastolic BP (DBP) before exercise (P < .01), whereas this difference was lost during exercise; (2) increased HR during the entire duration of exercise; and (3) significantly decreased SBP and DBP (P < .05) throughout the entire period of exercise.

Conclusions:

Exposure to a single exercise bout at moderate altitude is associated with a transient decrease in SBP and DBP, which is more pronounced in hypertensives.

Open access

Chad Seifried and Matthew Papatheodorou

The main purpose of this article is to provide suggestions to coaches on how they can assist young athletes in pressure packed situations to realize an ideal performance state. Suggestions provided address controlling emotions, adopting coping methods, practicing under game situations, embracing physical routines along with mental rehearsals, and engaging in self reflection/challenges. The strategies and discussions below should appear as vital for coaches attempting to help assist a young person’s future mental and emotional development. Furthermore, it should educate coaches and potentially others (e.g., spectators and media) on how to better handle these situations or instances so they can avoid the production of negative consequences on the lives of young people (e.g., choking label, social anxiety, poor self-esteem or image).

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Young-Shin Lee and Susan S. Levy

Objectives:

To examine physical activity (PA) in multiple contexts (household, walking, and leisure-time PA) and blood pressure (BP) across gender and income among older adults living independently.

Methods:

A convenience sample of 372 older adults completed 2 BP measurements and PA questionnaires.

Results:

Older adults with high incomes (≥$30,000) engaged in less household activity, more leisure time PA and better controlled their BP than those with low incomes (<$30,000). Men walked more than women. Older women in the low-income group had less controlled BP than those women in the high-income group. Participants with normal or controlled BP were engaged in more household and walking activities than those with uncontrolled BP.

Conclusion:

Findings suggest that older men and women at high or low-income levels have different mode of PA and BP management that should be considered for intervention strategies.

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Denise M. Hill, Nic Matthews and Ruth Senior

This study used qualitative methods to explore the stressors, appraisal mechanism, emotional response, and effective/ineffective coping strategies experienced by elite rugby union referees during pressurized performances. Participants included seven male rugby union referees from the United Kingdom (Mage = 27.85, SD = 4.56) who had been officiating as full-time professionals for between 1 and 16 years (M = 4.85, SD = 5.42). Data revealed that the referees encountered a number of stressors, which were appraised initially as a ‘threat’, and elicited negatively-toned emotions. The referees were able to maintain performance standards under pressure by adopting proactive, problem- and emotion-focused coping strategies which managed effectively the stressors and their emotions. However, the use of avoidance-coping, reactive control, and informal impression management were perceived as ineffective coping strategies, and associated with poor performance and choking. Recommendations are offered to inform the psychological skills training of rugby union referees.

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Gongbing Shan, Dayna Daniels and Rongri Gu

Numerous methods for studying the prevention of falls and age-related sensorimotor degradation have been proposed and tested. Some approaches are too impractical to use with seniors or too expensive for practitioners. Practitioners desire a simple, reliable technique. The goals of this research were to develop such an approach and to apply it in exploring the effect of Tai Chi on age-related sensorimotor degradation. The method employed artificial-neural-network (ANN) models trained by using individuals’ center-of-pressure (COP) measurements and age. Ninety-six White and Chinese adults without Tai Chi training were tested. In contrast, a third group, Chinese seniors with Tai Chi training, was tested to ascertain any influence from Tai Chi on sensorimotor aging. This study supported ANN technology with COP data as a feasible tool in the exploration of sensorimotor degradation and demonstrated that Tai Chi slowed down the effects of sensorimotor aging.

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Rita Santos-Rocha and António Veloso

Mechanical load has been estimated during step exercise based on ground reaction force (GRF) obtained by force platforms. It is not yet accurately known whether these measures reflect foot contact forces once the latter depend on footwear and are potentially modified by the compliant properties of the step bench. The aim of the study was to compare maximal and mean plantar pressure (PP), and maximal GRF obtained by pressure insoles after performing seven movements both over two metal force platforms and over the step bench. Fifteen step-experienced females performed the movements at the cadences of 130 and 140 beats per minute. PP and GRF (estimated from PP) obtained for each floor condition were compared. Maximal PP ranged from 29.27 ± 9.94 to 47.07 ± 12.88 N/cm2 as for metal platforms, and from 28.20 ± 9.32 to 43.00 ± 13.80 N/cm2 as for the step bench. Mean PP ranged from 11.09 ± 1.62 to 14.32 ± 2.06 N/cm2 (platforms) and from 10.71 ± 1.54 to 14.22 ± 1.77 N/cm2 (step bench). GRF (normalized body weight) ranged from 1.43 ± 0.14 to 2.41 ± 0.24 BW (platforms) and from 1.38 ± 0.14 to 2.36 ± 0.19 BW (step bench). No significant statistical differences were obtained for most of the comparisons between the two conditions tested. The results suggest that metal force platform surfaces are suitable to assess mechanical load during this physical activity. The forces applied to the foot are similar to the softer step bench and the hard force platform surface. This may reflect the ability of the performers to adapt their movement patterns to normalize the impact forces in different floor conditions.

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Deanna L. Huggett, Ian D. Elliott, Tom J. Overend and Anthony A. Vandervoort.

The authors compared heart-rate and blood-pressure responses to typical isometric (ISO) and isokinetic (90°/s) eccentric (ECC) resistance-training protocols in older adults. Twenty healthy older adults (74 ± 5 years old) performed randomly ordered ISO and isokinetic ECC exercise (3 sets of 10 repetitions) at a target intensity of 100% of their peak ISO torque value. Heart rate and systolic (SBP) and diastolic (DBP) blood pressures were recorded continuously, and mean arterial pressure (MAP) and rate-pressure product (RPP) were calculated. ECC peak torque (139 ± 33 N · m) was significantly greater than ISO peak torque (115 ± 26 N · m; p < .001). All variables increased significantly (p < .001) during both ISO and ECC exercise. Changes in SBP, DBP, MAP, and RPP were significantly greater during ISO exercise than during ECC exercise (p < .001). Clinically, an isokinetic ECC exercise program enables older adults to work at the same torque output with less cardiovascular stress than ISO exercise.

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Jane E. Yardley, Jacqueline Hay, Freya MacMillan, Kristy Wittmeier, Brandy Wicklow, Andrea MacIntosh and Jonathan McGavock

Type 2 diabetes is associated with hypertension and an increased risk of cardiovascular disease. In adults, blood pressure (BP) responses to exercise are predictive of these complications. To determine if the hemodynamic response to exercise is exaggerated in youth with dysglycemia (DG) compared with normoglycemic overweight/obese (OB) and healthy weight (HW) controls a cross-sectional comparison of BP and heart rate (HR) responses to graded exercise to exhaustion in participants was performed. DG and OB youth were matched for age, BMI z-score, height and sex. Systolic (SBP) and diastolic BP (DBP) were measured every 2 min, and HR was measured every 1 min. SBP was higher in OB and DG compared with HW youth at rest (p > .001). Despite working at lower relative workloads compared with HW, the BP response was elevated during exercise in OB and DG. For similar HR and oxygen consumption rates, BP responses to exercise were slightly higher in OB and DG compared with HW. OB and DG youth both display elevated resting and exercise BP relative to HW peers. Obesity may play a greater role than dysglycemia in the exaggerated BP response to exercise in youth.

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Hélène Perrault, Maria Tzovanis, Dominique Johnson, André Davignon, Claude Chartrand, Abdelkader Mokrane and Réginald A. Nadeau

This study compares the autonomic responses of 9 adolescents (mean ± SEM: 17±1 years) successfully operated for tetralogy of Fallot (TOF) in early childhood and 8 age-matched healthy controls (CTRL) using R-R and blood pressure variability. Continuous ECG and BP recordings were obtained during spontaneous and controlled respiration (CR) at 0.20 Hz as well as after an 85° head-up tilt (HUT) and during steady-state cycling at heart rates of 100 and 120 bpm, selected to reflect partial and complete cardiac vagal withdrawal. TOF exhibited total R-R variance and HF power (ms2) lower than CTRL under both spontaneous (938 ± 322 vs. 1,714 ± 296) and CR (1,541 ± 527 vs. 4,725 ± 1,207; p < .05), which may be indicative of a lower cardiac vagal activity. HUT decreased the R-R HF component, which remained lower in TOF than CTRL and increased the diastolic BP LF component in TOF but not in CTRL. Exercise decreased the R-R HF power more in TOF than CTRL. The exaggerated diastolic BP and limited heart rate responses to tilting and the more marked vagal withdrawal at Ex120 in TOF may be suggestive of a disturbance in the cardiac sympathetic response. Further studies are needed to confirm these observations on larger groups of young adults successfully operated for TOF.

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Brad Hodgson, Laurie Tis, Steven Cobb, Shawn McCarthy and Elizabeth Higbie

Context:

Because of research variability and the increasing use of orthotics to manage lower extremity problems, further research is warranted.

Objective:

To investigate the effect of rear-foot- and forefoot-posted (PAL) and mediolongitu-dinal arch-supported (SOLE) orthotics on plantar pressure (PP) during walking.

Design:

Repeated measures.

Setting:

Laboratory.

Participants:

17 subjects with forefoot varus.

Intervention:

Data were collected at 0 and 6 weeks for no-orthotic and orthotic conditions.

Measurements:

PPs were collected with the EMED Pedar measurement system.

Results:

Zero weeks: PAL increased PP in lateral forefoot (LFF), middle toes (MT), and lateral toes (LT) and decreased PP in lateral heel (LH), medial forefoot (MFF), and central forefoot (CFF). SOLE increased PP for midfoot (MF) and LT and decreased PP in medial heel (MH), LH, and CFF. 6 weeks: PAL increased PP in LFF, MT, and LT and decreased PP in LH, MFF, and CFF. SOLE increased PP in MF and decreased PP in MH, LH, and LFF.

Conclusion:

The SOLE orthotic appeared to be more effective in attaining the goals of custom-molded-orthotic intervention.