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2.
The aims of this study were to quantify the effects of factors such as mode of exercise, body composition and training on the relationship between heart rate and physical activity energy expenditure (measured in kJ x min(-1)) and to develop prediction equations for energy expenditure from heart rate. Regularly exercising individuals (n = 115; age 18-45 years, body mass 47-120 kg) underwent a test for maximal oxygen uptake (VO2max test), using incremental protocols on either a cycle ergometer or treadmill; VO2max ranged from 27 to 81 ml x kg(-1) x min(-1). The participants then completed three steady-state exercise stages on either the treadmill (10 min) or the cycle ergometer (15 min) at 35%, 62% and 80% of VO2max, corresponding to 57%, 77% and 90% of maximal heart rate. Heart rate and respiratory exchange ratio data were collected during each stage. A mixed-model analysis identified gender, heart rate, weight, V2max and age as factors that best predicted the relationship between heart rate and energy expenditure. The model (with the highest likelihood ratio) was used to estimate energy expenditure. The correlation coefficient (r) between the measured and estimated energy expenditure was 0.913. The model therefore accounted for 83.3% (R2) of the variance in energy expenditure in this sample. Because a measure of fitness, such as VO2max, is not always available, a model without VO2max included was also fitted. The correlation coefficient between the measured energy expenditure and estimates from the mixed model without VO2max was 0.857. It follows that the model without a fitness measure accounted for 73.4% of the variance in energy expenditure in this sample. Based on these results, we conclude that it is possible to estimate physical activity energy expenditure from heart rate in a group of individuals with a great deal of accuracy, after adjusting for age, gender, body mass and fitness.  相似文献   

3.
BackgroundRegular exercise is beneficial for adults with cardiovascular disease (CVD) and CVD risk factors. Tai Ji Quan is popular among older adults and may offer additional exercise options. The present article aims to review the scientific literature published within the past decade on Tai Ji Quan as an exercise modality to prevent and manage CVD.MethodsAn electronic literature search of four databases (PubMed, CINAHL, PsycINFO, and AMED) was conducted from April 2003 through March 2013. Studies that examined Tai Ji Quan, were published in English, and specified a target study population of participants with a known CVD condition (e.g., coronary artery disease, chronic heart failure, or stroke) or studies conducted among participants with a CVD risk factor (e.g., hypertension, dyslipidemia, or impaired glucose metabolism) were included.ResultsA total of 20 studies met the inclusion criteria: 11 randomized clinical trials, seven quasi-experimental studies and two cross-sectional studies. The effect of Tai Ji Quan was examined on more than 20 different study variables among persons with coronary artery disease (n = 5 studies), chronic heart failure (n = 5 studies), stroke (n = 4 studies), and CVD risk factors (n = 6 studies). These studies were conducted primarily in Asia (n = 9, 45%) or the United States (n = 8, 40%). Overall, participants enrolled in Tai Ji Quan had better outcomes, though mixed results were reported.ConclusionCollectively, these studies indicate that Tai Ji Quan is a safe form of exercise to prevent and manage CVD. Further research is needed with more rigorous study designs, larger sample sizes, adequate Tai Ji Quan exercise doses, and carefully chosen outcome measures that assess the mechanisms as well as the effects of Tai Ji Quan, before widespread recommendations can be made.  相似文献   

4.
体育活动与老年人的抑郁:系统综述   总被引：3，自引：1，他引：3  
抑郁是老年人一种常见的不良情绪，通过对描述性研究，元分析研究，流行病学研究和实验研究的综述，认为体育活动对减轻老年人的抑郁有积极作用。  相似文献   

5.
The aims of this study were to quantify the effects of factors such as mode of exercise, body composition and training on the relationship between heart rate and physical activity energy expenditure (measured in kJ?·?min?1) and to develop prediction equations for energy expenditure from heart rate. Regularly exercising individuals (n = 115; age 18?–?45 years, body mass 47?–?120?kg) underwent a test for maximal oxygen uptake ([Vdot]O2max test), using incremental protocols on either a cycle ergometer or treadmill; [Vdot]O2max ranged from 27 to 81?ml?·?kg?1?·?min?1. The participants then completed three steady-state exercise stages on either the treadmill (10?min) or the cycle ergometer (15?min) at 35%, 62% and 80% of [Vdot]O2max, corresponding to 57%, 77% and 90% of maximal heart rate. Heart rate and respiratory exchange ratio data were collected during each stage. A mixed-model analysis identified gender, heart rate, weight, [Vdot]2max and age as factors that best predicted the relationship between heart rate and energy expenditure. The model (with the highest likelihood ratio) was used to estimate energy expenditure. The correlation coefficient (r) between the measured and estimated energy expenditure was 0.913. The model therefore accounted for 83.3% (R 2) of the variance in energy expenditure in this sample. Because a measure of fitness, such as [Vdot]O2max, is not always available, a model without [Vdot]O2max included was also fitted. The correlation coefficient between the measured energy expenditure and estimates from the mixed model without [Vdot]O2max was 0.857. It follows that the model without a fitness measure accounted for 73.4% of the variance in energy expenditure in this sample. Based on these results, we conclude that it is possible to estimate physical activity energy expenditure from heart rate in a group of individuals with a great deal of accuracy, after adjusting for age, gender, body mass and fitness.  相似文献   

6.
ABSTRACT

There is a strong relationship between low physical activity level and cardiovascular diseases (CVD). The popularity of football may be used to promote physical activity and previous evidence has shown it is effective to decrease the risk of CVD. However, the energy expenditure (EE) of recreational football is not well known but it is crucial to develop preventive health programmes.

Fifteen sedentary middle-aged male participants were involved (mean ± SDs; age 43.9 ± 3.1 years, weight 83.0 ± 13.6 kg, height 174.9 ± 6.8 cm). EE was estimated from the heart rate (HR)-VO2 relation during 1-h 5-a-side matches (futsal). Participants covered 3412 ± 381 m in 52 ± 2 min, at an average HR of 85 ± 2% of maximum HR. Estimated EE during a recreational futsal match was 634 ± 92 kcal. One futsal recreational match corresponds to about 50% of American College of Sport Medicine recommended physical activity quantity per week. Based on this estimation: once, twice and 3 sessions per week are equivalent to 50% (634 kcal), 100% (1268 kcal) and 150% (1902 kcal), respectively, of EE suggested in international guidelines. This EE estimation may have important implications for designing recreational football training protocols in health programmes and dose response studies.  相似文献   

7.
The purpose of this study was to assess the accuracy of energy expenditure (EE) estimation and step tracking abilities of six activity monitors (AMs) in relation to indirect calorimetry and hand counted steps and assess the accuracy of the AMs between high and low fit individuals in order to assess the impact of exercise intensity. Fifty participants wore the Basis watch, Fitbit Flex, Polar FT7, Jawbone, Omron pedometer, and Actigraph during a maximal graded treadmill test. Correlations, intra-class correlations, and t-tests determined accuracy and agreement between AMs and criterions. The results indicate that the Omron, Fitbit, and Actigraph were accurate for measuring steps while the Basis and Jawbone significantly underestimated steps. All AMs were significantly correlated with indirect calorimetry, however, no devices showed agreement (p < .05). When comparing low and high fit groups, correlations between AMs and indirect calorimetry improved for the low fit group, suggesting AMs may be better at measuring EE at lower intensity exercise.  相似文献   

8.
The purpose of this study was to develop a multiple linear regression model to predict treadmill VO2max scores using both exercise and non-exercise data. One hundred five college-aged participants (53 male, 52 female) successfully completed a submaximal cycle ergometer test and a maximal graded exercise test on a motorized treadmill. The submaximal cycle protocol required participants to achieve a steady-state heart rate equal to at least 70% of age-predicted maximum heart rate (220-age), while the maximal treadmill graded exercise test required participants to exercise to volitional fatigue. Relevant submaximal cycle ergometer test data included a mean (±SD) ending steady-state heart rate and ending workrate equal to 164.2 ± 13.0 bpm and 115.3 ± 27.0 watts, respectively. Relevant non-exercise data included a mean (±SD) body mass (kg), perceived functional ability score, and physical activity rating score of 74.2 ± 15.1, 15.7 ± 4.3, and 4.7 ± 2.1, respectively. Multiple linear regression was used to generate the following prediction of (R = .91, standard error of estimates (SEE) = 3.36 ml·kg?1·min?1): VO2max = 54.513 + 9.752 (gender, 1 = male, 0 = female) – .297 (body mass, kg) + .739 (perceived functional ability, 2–26) + .077 (work rate, watts) – .072 (steady-state heart rate). Each predictor variable was statistically significant (p < .05) with beta weights for gender, body mass, perceived functional ability, exercise workrate, and steady-state heart rate equal to .594, –.544, .388, .305, and –.116, respectively. The predicted residual sums of squares (PRESS) statistics reflected minimal shrinkage (RPRESS = .90, SEEPRESS = 3.56 ml·kg?1·min?1) for the multiple linear regression model. In summary, the submaximal cycle ergometer protocol and accompanying prediction model yield relatively accurate VO2max estimates in healthy college-aged participants using both exercise and non-exercise data.  相似文献   

9.
Regarding the phenomenon of mood improvements through physical exercise, secondary analyses indicate that improvements can hardly be generalised. Rather, personal and situational factors need to be taken into consideration in order to define the effects in a more precise manner. This contribution investigates to what extent explicit motives and goals of individuals in middle adulthood can be considered as personal moderators of mood changes. Five exercise programmes were developed in a quasi-experimental design and were conducted over a 3-month intervention period. These programmes were based on the “motive-based types of sportsperson” (Sudeck, Lehnert & Conzelmann, 2011), which define groups of individuals with similar motive and goal profiles. One hundred and thirty-three individuals participated in either a programme tailor-made to their motive and goal profile or in a non-tailored programme. The influence of this motive-based tailoring was investigated based on the mood dimensions of valence, calmness and positive activation using handheld PCs during and after exercise sessions. Results indicate a moderating influence of explicit motives and goals. This moderation was however not a general one but rather depended on the exercise programmes’ specific goals and content as well as on individuals’ goals regarding recreation. These findings point towards a systematic consideration of explicit motives and goals in the planning of health and leisure sport programmes.  相似文献   

10.
The physiology of deep-water running   总被引：2，自引：0，他引：2  
Deep-water running is performed in the deep end of a swimming pool, normally with the aid of a flotation vest. The method is used for purposes of preventing injury and promoting recovery from strenuous exercise and as a form of supplementary training for cardiovascular fitness. Both stroke volume and cardiac output increase during water immersion: an increase in blood volume largely offsets the cardiac decelerating reflex at rest. At submaximal exercise intensities, blood lactate responses to exercise during deep-water running are elevated in comparison to treadmill running at a given oxygen uptake (VO2). While VO2, minute ventilation and heart rate are decreased under maximal exercise conditions in the water, deep-water running nevertheless can be justified as providing an adequate stimulus for cardiovascular training. Responses to training programmes have confirmed the efficacy of deep-water running, although positive responses are most evident when measured in a water-based test. Aerobic performance is maintained with deep-water running for up to 6 weeks in trained endurance athletes; sedentary individuals benefit more than athletes in improving maximal oxygen uptake. There is some limited evidence of improvement in anaerobic measures and in upper body strength in individuals engaging in deep-water running. A reduction in spinal loading constitutes a role for deep-water running in the prevention of injury, while an alleviation of muscle soreness confirms its value in recovery training. Further research into the applications of deep-water running to exercise therapy and athletes' training is recommended.  相似文献   

11.
Abstract

The purpose of this study was to determine the ability of individuals with a cervical spinal cord injury to achieve and sustain a cardiorespiratory training intensity during wheelchair rugby. Nine wheelchair rugby players completed a continuous peak exercise test on a SciFit Pro I arm ergometer with stage increases each minute to determine peak heart rate and power output. Approximately one week after peak exercise testing, heart rate was recorded (every 5 s) during three regularly scheduled rugby training sessions. Data were analysed to determine the number of continuous minutes that participants spent above 70% of heart rate reserve under various rugby training activities. The percent of time spent at or above 70% heart rate reserve varied across participants and conditions. Continuous pushing was the least variable training condition among participants with the sample averaging greater than 73% of time above the target heart rate. Scrimmage training was highly variable across participants with a range of 0% to 98% of time above the criterion. Results of this study indicate that wheelchair rugby training enables some participants to reach a training intensity associated with improved cardiorespiratory fitness, and that the type (or kind) of training activity dictates the extent to which individuals sustain such a threshold.  相似文献   

12.
Abstract

Walking is the most natural physical activity to maintain and improve fitness and health. Walking downhill is usefully adopted to plan training programmes to improve the strength, particularly in older adults. The present research was aimed to evaluate the influence of downhill walking on leg strength in young adult. A total of 32 females (age 26 ± 4 years; height 1.64 ± 0.05 m; body mass 57.6 ± 5.6 kg) were divided into four groups and they carried out an exercise intervention consisting of three sessions per week for 6 weeks, each lasting 30 minutes. Groups were defined at several workloads characterised by treadmill inclination (%) and walking speed (m·s?1): Level Walking at treadmill inclination 0% and walking speed 1.0; Uphill Walking at +20%, 0.75; Downhill Walking (DW) at ?20%, 1.36; and Mixed Walking at +20%, 0.75 and ?20%, 1.36 each lasting 15 minutes. Maximum voluntary contraction (MVC) developed by the Quadriceps Femoris and Endurance Time at 60% MVC were evaluated before and after experimental period. At the end of each session, Borg's scale and Visual Analogue Scale (VAS) were adopted in order to evaluate perception of rate exertion and pain. Statistical analysis showed significant only in MVC for DW in both right and left legs. Borg's scale and VAS described light activity free of pain. Present findings showed how an eccentric exercise, short lasting and at a low workload, can be useful in inducing improvements in leg strength.  相似文献   

13.
Epidemiological and experimental studies have suggested that dietary salt may play a role in airway responsiveness. We have previously shown that a low salt diet improves and a high salt diet exacerbates post-exercise pulmonary function in individuals with exercise-induced asthma. The aim of this study was to determine the influence of both elevated and restricted salt diets on pulmonary function during exercise in individuals with exercise-induced asthma. Nine men and six women participated in this double-blind, crossover study. The participants entered the study on their normal salt diet and were placed on either a low or high salt diet for 2 weeks. Each diet was randomized, with a 1 week washout period between diets before crossing over to the alternative diet for 2 weeks. The participants underwent treadmill testing at 85% of their age-predicted heart rate on the normal salt diet and at the end of each treatment period. Pulmonary function was assessed during exercise by arterial saturation (ear oximetry) and indirect calorimetry. Twenty-four hour urine collections confirmed compliance with the diets. Arterial saturation was reduced on the high and improved on the low salt diet at higher exercise intensities. Tidal volume and frequency selection during exercise varied with the diets, with a higher tidal volume and lower frequency on the high salt diet, but a lower tidal volume and higher frequency on the low salt diet. This suggested greater airway resistance during the high salt diet. In conclusion, the low salt diet improved and the high salt diet exacerbated pulmonary function during exercise in individuals with exercise-induced asthma. The mechanism of action remains unclear.  相似文献   

14.
Individuals with schizophrenia have a greater risk for cardiometabolic risk factors (e.g. central obesity, insulin resistance, hypertension and dyslipidaemia), cardiovascular diseases and mortality. This risky profile may be explained by the adverse effects of antipsychotic medications and an unhealthy lifestyle (e.g. smoking, poor nutrition and low physical activity). In the general population, physical activity has been shown to be the optimal strategy to improve both cardiometabolic parameters and cardiorespiratory fitness levels. Accordingly, an emerging literature of non-pharmacological interventions (e.g. cognitive behavioural therapy, diet and physical activity) has been studied in individuals with schizophrenia. Therefore, the purpose of this review was 1) to conduct a critical literature review of non-pharmacological interventions that included some kind of physical activity (including supervised and unsupervised exercise training) and target cardiometabolic risk factors in individuals with schizophrenia. 2) To describe the contribution of physical activity alone by reviewing trials of supervised exercise training programmes only. A literature review via systematic keyword search for publications in Medline, PubMed, Embase and PsycINFO was performed. Many non-pharmacological interventions are efficient in reducing cardiovascular disease risk factors when combined with physical activity. Supervised physical activity has been successful in decreasing cardiovascular disease risk, and aerobic interval training appears to provide more benefits by specifically targeting cardiorespiratory fitness levels. In conclusion, physical activity is an effective strategy for addressing cardiovascular disease risk in individuals with schizophrenia. Long-term studies are needed to evaluate the feasibility and impact of exercise training programmes in individuals with schizophrenia.  相似文献   

15.
Despite females consistently reporting greater social physique anxiety (SPA), previous literature has yet to demonstrate whether SPA gender differences are linked to the way males and females perform physical activity. This study investigated an association between SPA and physical activity frequency, history of exercise, and physical activity intensity. Participants were represented by currently active users (N?=?33 males; N?=?31 females) of an on-campus university-run gym and completed a background physical activity questionnaire and the nine-item Social Physique Anxiety Scale. Participants also performed an exercise session at a self-selected level of exertion, with the intensity of each session measured via heart rate monitor. SPA was not associated with physical activity frequency, history of exercise (length of gym membership), or intensity for male and female exercisers. With respect to male participants, females reported higher SPA and a preference for performing higher intensity physical activity. Females and males also indicated a preference for performing aerobic and anaerobic physical activity respectively. Our findings suggest the experience of SPA does not deter body-conscious individuals from the performance of regular physical activity. Findings also suggest the discrepancy in male and female SPA is not linked to differences in the way physical activity is performed.  相似文献   

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目的探讨相对运动强度和绝对运动强度对血清酶活性变化的影响。实验方法受试者为急性心肌梗塞康复病人(PMIP)和正常人(HS) ,实验前后测定了他们血清乳酸脱氢酶(L DH)、乳酸脱氢酶同工酶1(L DH- 1)、肌酸激酶(CK)、肌酸激酶亚单位MB(CK- MB)活性。结果两组受试者运动前酶的活性均无显著差异(P>0 .0 5 ) ;实验中,PMIP与HS的相对强度分别为最大心率的85 .1%、86 .0 % (P>0 .0 5 ) ,绝对强度分别为跑台等级的5 .3与6 .3(P<0 .0 5 ) ,PMIP与HS运动后即刻酶活性与运动前相比均有显著上升(P<0 .0 5 ) ,但两组间无显著差异(P>0 .0 5 ) ,2 4 h后HS组的酶活性基本恢复到运动前水平,但PMIP组仍高于运动前水平。结论运动后酶活性上升的幅度与运动所达到的相对强度有关;强度达85 % HRmax的运动能引起血清酶活性的升高,但此时L DH- 1/L DH和CK- MB/CK的比值与运动前相比无明显变化;如果PMIP的康复运动量等同于测试中的运动量,他们第2天似应停止活动以便能够得到充分的恢复。  相似文献   

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The number of older adults (individuals ≥65 years), particularly women, in our society is increasing and understanding the impact of exercise on muscle capacity (e.g., strength and power) and subsequently physical function is of utmost importance to prevent disability and maintain independence. Muscle capacity declines with age and this change negatively impacts physical function in older women. Exercise, specifically resistance training, is recommended to counteract these declines; however, the synergistic relationships between exercise, muscle capacity, and physical function are poorly understood. This review will summarize the literature regarding age-related changes in the aforementioned variables and review the research on the impact of resistance training interventions on muscle capacity and physical function in older women. Recommendations for future research in this area will be discussed.  相似文献   

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