Search Results

You are looking at 1 - 10 of 5,299 items for :

  • "intensity" x
  • Refine by Access: All Content x
Clear All
Restricted access

Julian David Pillay, Tracy Lynn Kolbe-Alexander, Willem van Mechelen, and Estelle Victoria Lambert

Background:

Pedometer-based recommendations for accumulating steps/d largely focus on volume, with less emphasis on intensity and fitness/health outcomes. We aim to examine this relationship.

Methods:

A convenience sample (N = 70, 35 men, 32 ± 8yrs) wore a pedometer (4 days). The pedometer classified steps as “aerobic” (≥ 60 steps/minute, minimum duration of 1 minute) or “non-aerobic” (< 60 steps/minute and/or < 1 minute). Estimated maximal oxygen uptake (VO2max), derived from a 12-minute submaximal step-test, and health outcomes: blood pressure (BP), body mass index (BMI), percentage body fat (%BF), and waist circumference (WC) were correlated with pedometer data. Participants were grouped according to number and intensity of steps: LOW (< 5000 steps/d), HIGH-LOW (≥ 5000 steps/d, no aerobic steps), HIGH-HIGH (≥ 5000 steps/d, including some aerobic steps). Analyses of covariance, adjusting for age, gender, and total steps/d were used to compare groups.

Results:

Average steps/d was 6520 ± 2306. Total steps/d and total time spent accumulating “aerobic” steps (minutes/day) were inversely associated with %BF, BMI, WC, and systolic BP (P < .05). After adjusting for gender and total steps/d, %BF was different between all 3 groups, VO2max was different between the LOW and HIGH-HIGH groups, WC was lower in the HIGH-HIGH versus the other 2 groups (P < .03, respectively).

Conclusion:

Intensity seems an important factor to consider in steps/d cut-points.

Restricted access

Esther Morencos, Blanca Romero-Moraleda, Carlo Castagna, and David Casamichana

In recent years, global positioning system (GPS) analysis has become a widely used tool for quantifying competition demands, informing training prescription, and monitoring the training stimulus. 1 In team sports such as hockey, considered as intermittent, high-intensity activity, 2 reductions in

Restricted access

Jane Jie Yu, Chia-Liang Tsai, Chien-Yu Pan, Ru Li, and Cindy Hui-Ping Sit

because of the importance of the childhood period for brain growth in terms of structure and function and the rise of physical inactivity in children worldwide. 3 It is recommended that all children and youth do 60 minutes or more of moderate to vigorous PA daily, 4 which includes vigorous-intensity

Restricted access

Alejandro Martínez-Cava, Alejandro Hernández-Belmonte, and Jesús G. Pallarés

kept constant through the RT intervention. The %1RM used by this group in all sessions (77.5%) corresponded to the average intensity trained by the rest of the models throughout the training cycle. Figure 1 —Evolution of the relative intensity (%1RM) and intraset volume throughout the training program

Restricted access

Miguel Sánchez-Moreno, Luis Rodiles-Guerrero, Gonçalo Rendeiro-Pinho, António Prieto-Veloso, and Fernando Pareja-Blanco

as follows: volume load (in arbitrary units) = number of sets × number of repetitions × %1RM. Volume load is related to measures of internal workload and physiological response during RT at various intensities 7 and is typically used to compare RT protocols with different configurations. 8 However

Restricted access

Neha Singhal and Anupa Siddhu

Background:

The relationship between leisure-time physical activity (LTPA) and cardiorespiratory fitness (CRF) is not clearly understood in Indian men. It is important to elucidate whether the duration or intensity of LTPA is responsible for increasing CRF. This will help in designing better physical activity intervention strategies for improving CRF in Indian men.

Methods:

Healthy nondiabetic urban Indian men with no history of coronary heart disease (CHD) were selected (n = 603; aged 22–64 years) and their energy intake and physical activity was determined using a questionnaire. Body fat (percent) was determined by leg-to-leg bioelectrical impedance analysis while CRF was measured on multistage, continuous treadmill test using Bruce protocol.

Results:

Intensity of physical activity (METs) emerged as the best independent predictor of CRF (β = 0.217; P < .001). Using univariate General Linear Model, it was found that CRF is more a function of LTPA intensity than LTPA duration, since LTPA duration was not related to CRF when controlled for LTPA intensity. However, LTPA intensity remained significantly associated with CRF even after adjustment for LTPA duration.

Conclusion:

LTPA of preferably higher intensity should be incorporated in the lifestyle to improve CRF and prevent CHD in Indian men.

Restricted access

Shawn M. Arent, Daniel M. Landers, Kathleen S. Matt, and Jennifer L. Etnier

The purpose of this study was to examine the dose-response gradient of exercise-induced affective change and the role of the stress response as a contributing mechanism. Male and female participants (N = 31) completed three different resistance training protocols (40%, 70%, and 100% of 10-repetition maximum [RM]) and a no-treatment control condition. Affective responses were assessed immediately before and at 0–5, 15, 30, 45, and 60 minutes postexercise. Salivary cortisol and heart rate (HR) responses were also assessed during each condition. As predicted, moderate intensity resistance training generally produced the greatest improvements in affect (p < .05). HR and cortisol accounted for as much as 27.3% and 5.4% of the affective variance, respectively. Findings support a curvilinear dose-response relationship between intensity and affective responses, with moderate intensity training resulting in immediate, large, and enduring affective benefits. Results also suggest that moderate activation of the stress response positively influences exercise-induced affective change.

Restricted access

Renato Barroso, Ronaldo K. Cardoso, Everton Crivoi Carmo, and Valmor Tricoli

Session rating of perceived exertion (SRPE) is a practical method to assess internal training load to provide appropriate stimuli. However, coaches and athletes might rate training sessions differently, which can impair performance development. In addition, SRPE might be influenced by athletes’ training experience. The authors studied 160 swimmers of different age groups and different competitive swimming experience and 9 coaches. SRPE was indicated by the swimmers 30 min after the end of a training session and before the training session by the coaches. Training-session intensities were classified into easy (SRPE <3), moderate (SRPE 3–5), and difficult (SRPE >5), based on coaches’ perception. We observed that the correlation between coaches’ and athletes’ SRPE increased with increased age and competitive swimming experience, r = .31 for the 11- to 12-y-old group (P < .001), r = .51 for the 13- to 14-y-old group (P < .001), and r = .74 for the 15- to 16-y-old group (P < .001). In addition, younger swimmers (11–12 y, P < .01; 13–14 y, P < .01) rated training intensity differently from coaches in all 3 categories (easy, moderate, and difficult), while the older group rated differently in only 1 category (difficult, P < .01). These findings suggest that the more experienced swimmers are, the more accurate their SRPE is.

Restricted access

Vasilios I. Kalapotharakos, Maria Michalopoulou, George Godolias, Savvas P. Tokmakidis, Paraskevi V. Malliou, and Vasilios Gourgoulis

The purpose of this study was to investigate the effects of a 12-week resistance-training program on muscle strength and mass in older adults. Thirty-three inactive participants (60–74 years old) were assigned to 1 of 3 groups: high-resistance training (HT), moderate-resistance training (MT), and control. After the training period, both HT and MT significantly increased 1-RM body strength, the peak torque of knee extensors and flexors, and the midthigh cross-sectional area of the total muscle. In addition, both HT and MT significantly decreased the abdominal circumference. HT was more effective in increasing 1-RM strength, muscle mass, and peak knee-flexor torque than was MT. These data suggest that muscle strength and mass can be improved in the elderly with both high- and moderate-intensity resistance training, but high-resistance training can lead to greater strength gains and hypertrophy than can moderate-resistance training.

Restricted access

James J. McClain, Teresa L. Hart, Renee S. Getz, and Catrine Tudor-Locke

Background:

This study evaluated the utility of several lower cost physical activity (PA) assessment instruments for detecting PA volume (steps) and intensity (time in MVPA or activity time) using convergent methods of assessment.

Methods:

Participants included 26 adults (9 male) age 27.3 ± 7.1 years with a BMI of 23.8 ± 2.8 kg/m2. Instruments evaluated included the Omron HJ-151 (OM), New Lifestyles NL-1000 (NL), Walk4Life W4L Pro (W4L), and ActiGraph GT1M (AG). Participants wore all instruments during a laboratory phase, consisting of 10 single minute treadmill walking bouts ranging in speed from 40 to 112 m/min, and immediate following the laboratory phase and during the remainder of their free-living day (11.3 ± 1.5 hours). Previously validated AG MVPA cutpoints were used for comparison with OM, NL, and W4L MVPA or activity time outputs during the laboratory and free-living phase.

Results:

OM and NL produced similar MVPA estimates during free-living to commonly used AG walking cutpoints, and W4L activity time estimates were similar to one AG lifestyle cutpoint evaluated.

Conclusion:

Current findings indicate that the OM, NL, and W4L, ranging in price from $15 to $49, can provide reasonable estimates of free-living MVPA or activity time in comparison with a range of AG walking and lifestyle cutpoints.