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1.
Int J Exerc Sci ; 16(2): 252-266, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37114194

RESUMO

Astaxanthin (AX) is an antioxidant which may spare endogenous carbohydrates and improve fat oxidation rates, thus improving metabolic flexibility. To date, no studies have attempted to examine the impact of AX in an overweight cohort, whom often suffer from metabolic inflexibility. Nineteen subjects (mean ± SD: age: 27.5 ± 6.3 years; height: 169.7 ± 9.0 cm; body mass: 96.4 ± 17.9 kg; BF%: 37.9 ± 7.0%; BMI: 33.4 ± 5.6 kg/m2; VO2peak: 25.9 ± 6.7 ml·kg-1·min-1) were recruited and supplemented with either 12 mg of AX or placebo (PLA) for 4 weeks. Subjects completed a graded exercise test on a cycling ergometer to examine changes in substrate oxidation rates. A total of 5 stages, each lasting 5 min and resistance increased 15 W each stage, were completed to examine changes in levels of glucose and lactate, fat and carbohydrate (CHO) oxidation rates, heart rate, and rating of perceived exertion (RPE). Although there were no changes found in rates of fat oxidation, blood lactate or glucose, or RPE (all p > 0.05), a significant decrease was observed in CHO oxidation from pre to post supplementation in the AX group only. Further, the AX group demonstrated a 7% decrease in heart rate across the graded exercise test. These findings suggest that 4 weeks of AX supplementation may offer some cardiometabolic benefits to overweight individuals, and be a favorable supplement for these individuals beginning an exercise program.

2.
Int J Exerc Sci ; 16(4): 1066-1076, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288073

RESUMO

This study investigated the influence of yoga breathing techniques (YBT) on physiological and perceptual responses during sub-maximal treadmill running. Runners (n = 21) of various fitness (VO2max 48.4 ± 9.5 ml/kg/min) were assigned to Yoga (YG) or control (CT) group before completing pre/post treadmill trials where velocity was self-selected to produce an RPE 4 and RPE 7 (10 min each). YG (n =11) practiced three styles of YBT (30 min/day, 6 days/wk) for 3 consecutive wks. Self-selected running velocity for YG improved significantly at both prescribed RPE 4 (pre 157.63 ± 26.20 M/min, post 181.02 ± 24.22 M/min, p = 0.01) and prescribed RPE 7 (pre 201.97 ± 31.28 M/min, post 222.68± 35.32 M/min, p = 0.01). VO2 at RPE 7 increased significantly (pre 42.6 ± 6.9 ml/kg/min, post 47.3 ± 6.2 ml/kg/min, p = 0.02), TV at RPE 7 (pre 1.81 ± 0.30, post 2.04 ± 0.41, p = 0.01), and MV at RPE 7 (pre 77.25 ± 12.42, post 91.23 ± 20.05, p = 0.01). The CT group showed no significant changes except for TV at RPE 7 (pre 1.9 ± 0.3, post 2.0 ± 0.3, p = 0.04). Current results suggest YBT positively influences running velocity regulation during self-selected running.

3.
J Strength Cond Res ; 36(7): 1833-1838, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32910072

RESUMO

ABSTRACT: Sharp, DW, Swain, JC, Boy, TG, Killen, LG, Green, JM, and O'Neal, EK. Effects of 2.4 kg of proximal external loading on 5-km running performance. J Strength Cond Res 36(7): 1833-1838, 2022-Racing weight is a popular topic in the running community. This study examined effects of modest loading via a ∼2.4-kg soft and malleable weighted compression garment on overground running performance. Former and current collegiate cross-country runners (5 women and 6 men) completed 2 outdoor, solo road course runs 7 days apart on a familiar training route. During the first run (CON) subjects ran as closely as possible to their goal pace for a "hard speed day" workout based on predetermined paces according to current training level. During a subsequent run, subjects attempted to match their pace with aid from global positioning system watches and splits verbally announced on the course while wearing the weighted compression garment (LOAD). Metabolic data was later assessed during 5-minute running bouts on a treadmill with CON and LOAD conditions at subject's CON run pace. LOAD was slower (p < 0.01) at the 1.6-km mark (6:03 ± 0:37 vs. 6:13 ± 0:40) and finish (18:29 ± 2:06 vs. 19:15 ± 2:16). There was no differentiation (p > 0.05) between V̇o2 (CON 3.47 ± 0.86; LOAD 3.56 ± 0.77 L·min-1) or respiratory exchange ratio (CON 1.05 ± 0.06; LOAD 1.06 ± 0.04) during the 5-minute running economy bouts. There was an inverse (r = -0.42) but nonsignificant (p = 0.22) relationship between percent difference in body mass and percent difference in performance. Metabolic variable differentiation was not detectable at race pace, but 2.4 kg of proximal loading resulted in an approximately 4% acute performance impairment.


Assuntos
Teste de Esforço , Consumo de Oxigênio , Vestuário , Feminino , Humanos , Masculino
4.
Int J Exerc Sci ; 14(2): 1375-1387, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096234

RESUMO

Caffeine (CAF) has been extensively studied for its ergogenic and analgesic effects during exercise. However, the majority of these studies have been conducted in male populations. This study investigated the effects of acute CAF chewing gum on self-selected exercise intensity during a rating of perceived exertion (RPE) production trial in active females (n = 16, 21.0 ± 2.8 y). Data were also analyzed based on habitual CAF consumption level. Participants completed a V̇O2peak trial, followed by a familiarization and two randomized, triple-blinded experimental RPE production trials on an arm ergometer [clamped resistance, blinded to self-selected cadence (CAD)] with either CAF gum (300 mg; 4.8 ± 0.7 mg/kg-1 body mass) or placebo (PLA), at a prescribed RPE of 4 and 7 (10 min each). Self-selected CAD did not statistically differ (p > 0.05) between CAF or PLA for an RPE4 (37.7 ± 1.6 vs. 37.6 ± 1.6 rev·min-1) or RPE7 (42.9 ± 1.6 vs. 41.2 ± 1.7 rev·min-1), respectively. There were no statistical differences between treatment groups for any other variables, except restlessness rating which was significantly higher (3.5 vs. 2.2; p = 0.03, d = 0.64) for the CAF group compared to PLA. Secondary analysis revealed no statistical differences for any variables between habitual consumers of low (23 ± 20 mg/day) or mod/high (195 ± 93 mg/day) CAF. Our data support previous studies examining CAF in women across different testing modalities and suggest that regardless of habitual CAF consumption, females might require higher doses of CAF to replicate subjective and physiological responses commonly observed using similar RPE production protocols in male participants. These findings support the need for additional investigations into female physiological and perceptual responses following CAF ingestion.

5.
Int J Exerc Sci ; 13(2): 62-74, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32148615

RESUMO

Yogic breathing techniques (Pranayama) positively impact respiratory function (RF) in non-endurance trained individuals. The purpose of this study investigated effects of routine Pranayama practice on RF, running economy (RE) and perceptual responses. A between subject's case-control study design was incorporated. Eleven runners practiced three styles of Pranayama (30 min/day 6 days/week) for 3 consecutive weeks (YG) and completed a VO2 max tests on a treadmill (trial 1), basic RF tests, and constant workload RE trials at 60, 70, and 80% VO2 max (trial 2 and 3). A control group (n = 10) (CT) completed the same pre - post testing without intervention. Pre vs. post values for resting forced vital capacity (FVC), peak expiratory flow rate (PEFR) and forced expiratory flow volume in one second (FEV1). Yoga improved FVC and FEV1, but did not significantly impact RE However, RPE-L for HIGH had an interaction (p < 0.05) showing a decrease for YG and an increase for CT. The current study suggests 3 weeks of yogic Pranayama fails to significantly impact RE, however some evidence indicates YG may positively alter perceptual responses at individually prescribed workloads. More work is needed to definitively establish benefits of YG for runners.

6.
J Strength Cond Res ; 34(5): 1383-1391, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-29489724

RESUMO

Kraft, JA, Laurent, ML, Green, JM, Helm, J, Roberts, C, and Holt, S. Examination of coach and player perceptions of recovery and exertion. J Strength Cond Res 34(5): 1383-1391, 2020-Monitoring training and recovery are essential for exercise programming. Athletes can validly assess training load (TL) via the session rating of perceived exertion (SRPE) technique. However, it is unclear if coaches can successfully use this model. This study compared coach and athlete perceptions of effort and recovery, and it evaluated the efficacy of perceptually based TL monitoring. Participants included 56 athletes (Women's volleyball, soccer, and basketball and Men's basketball) and their coaches (n = 4). Perceived recovery was estimated via the Perceived Recovery Status scale. Scores of TL were calculated using the Edward's heart rate (HR) method and by multiplying SRPE by duration. Coaches provided an intended SRPE (SRPE-CI) before practice. Also, SRPE was independently estimated by coaches (SRPE-CO) and athletes (SRPE-A) ∼15-20 minutes after practice. Paired t-tests and Pearson's correlations were applied to make comparisons (α ≤ 0.05). Values of SRPE-CI, SRPE-CO, SRPE-A TLs were strongly correlated with Edwards' HR-based TLs (R = 0.74, 0.73, and 0.76, respectively). However, SRPE-CI (5.5 ± 1.9) and SRPE-CO (5.0 ± 1.9) was higher than SRPE-A (4.5 ± 1.9). Coaches estimated recovery higher than athletes (7.1 ± 1.3 vs. 5.8 ± 1.6). Estimates of TL strongly correlated with Edwards' TL regardless of information source (coach or athlete) or time point (SRPE-CI TL or SRPE-CO TL). Results suggest that coaches' perceptions validly indicated TL. Coaches' perceptions provide parallel information (correlated strongly with Edwards TL) but not identical information (demonstrated by differences in SRPE) as athlete perceptions. Differences in perceived recovery indicate that coaches overestimate recovery when compared with athletes' perceptions.


Assuntos
Atletas/psicologia , Tutoria , Condicionamento Físico Humano/fisiologia , Condicionamento Físico Humano/psicologia , Esforço Físico/fisiologia , Adulto , Algoritmos , Exercício Físico/fisiologia , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Condicionamento Físico Humano/métodos , Adulto Jovem
7.
Int J Exerc Sci ; 12(6): 1290-1301, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31839857

RESUMO

This study examined the effects of caffeine on tennis serve accuracy. Division II tennis athletes (n = 10) completed two serve trials (double-blind, counterbalanced) following ingestion of 6 mg/kg of caffeine or matched placebo an hour prior to data collection. During each tennis serve trial, participants completed 48 non-fault serves divided into 3 sets with 2 serves per 8 different targets. Following each 2 serves per target format, participants completed a shuttle run sprint. Separate 2 (trial) × 8 (targets) repeated measures analysis of variances (ANOVAs) were used for distances from the target center "delta", and necessary tries for each of the 3 sets. A 2 (treatment) × 3 (set) repeated measures ANOVA was used for shuttle run times. While results were not significant, the treatment main effect approached significance (p = 0.07) in set 2 for the delta of distances when comparing caffeine (96.2 cm ± 19.8) versus placebo (107.1 cm ± 16.3). While there was no significance in sprint times, each sprint was consistently faster following caffeine consumption. Post-trial surveys revealed subjective responses approached significance with greater feelings of stomach distress (p = 0.08) and nervousness (p = 0.13) following caffeine and elevated feeling of fatigue (p = 0.19) following placebo. Therefore, with no impairment in serve accuracy coupled with some evidence of reduced fatigue, results suggest caffeine may benefit tennis athletes. Extending the understanding of the effects of caffeine on tennis serve accuracy and performance could benefit overall match performance, with the potential of improving the match outcome in extended playtime.

8.
J Strength Cond Res ; 32(7): 2066-2071, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29239983

RESUMO

Green, JM, Miller, B, Simpson, J, Dubroc, D, Keyes, A, Neal, K, Gann, J, and Andre, T. Effects of 2% dehydration on lactate concentration during constant-load cycling. J Strength Cond Res 32(7): 2066-2071, 2018-The lactate [La] threshold (LT) can predict endurance performance potential. Dehydration may alter LT. This study examined effects of dehydration on [La] response during constant-load cycling. Recreationally fit (V[Combining Dot Above]O2peak = 48.7 ± 5.2 ml·kg·min) male participants (n = 9) completed 2 × 40-minute constant-load cycling trials; euhydrated (HYD) and after previous evening passive (water bath) dehydration (2% body weight, DEH) (HYD and DEH counterbalanced). Lactate, heart rate (HR), 10-point Omni ratings of perceived exertion (RPE), and rectal temperature (Trec) were measured after warm-up (WU) and at 10, 20, 30, and 40 minutes. Before cycling, urine specific gravity (USG) was measured and participants estimated perceived recovery status (PRS). Urine specific gravity DEH (1.027 ± 0.004) was significantly greater than HYD (1.013 ± 0.007). After WU, [La] was significantly greater (all time points) for DEH (∼4.1 mmol·L) vs. HYD (∼3.5 mmol·L) with similar results for HR (DEH: ∼167, HYD: ∼158 b·min). For DEH, RPE was significantly greater (∼1 unit) at 20, 30, and 40 minutes, and Trec was significantly greater at 30 and 40 minutes (∼0.4° C). DEH (vs. HYD) also resulted in significantly different resting HR (93 ± 6, vs. 85 ± 7 b·min), significantly greater session RPE (7.7 ± 1.1 vs. 5.3 ± 1.1), and significantly lower subjective feelings of recovery (PRS = 6.4 ± 2.9, vs. 9.0 ± 1.5). Current results indicate systematic changes in [La] and associated physiological responses result from previous day dehydration. Hydration status should be a concern in paradigms where [La] assessment is used.


Assuntos
Ciclismo/fisiologia , Desidratação/sangue , Ácido Láctico/sangue , Adulto , Temperatura Corporal/fisiologia , Desidratação/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Adulto Jovem
9.
Appl Physiol Nutr Metab ; 41(10): 1077-1082, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27704869

RESUMO

Caffeine (CAF) blunts estimated ratings of perceived exertion (RPE) but the effects on RPE production are unclear. This study examined effects of acute caffeine ingestion during treadmill exercise where participants exercised at prescribed RPE 4 and 7. Recreational runners (maximal oxygen consumption = 51.4 ± 9.8 mL·kg-1·min-1) (n = 16) completed a maximal treadmill test followed by trials where they selected treadmill velocity (VEL) (1% grade) to produce RPE 4 and RPE 7 (10 min each). RPE production trials followed CAF (6 mg·kg-1) or placebo (PLA) (counterbalanced) ingestion. Participants were blinded to treadmill VEL but the Omni RPE scale was in full view. Repeated-measures ANOVA showed a main effect (trial) for VEL (CAF ∼5 m·min-1 faster) for RPE 4 (p = 0.07) and RPE 7 (p = 0.03). Mean heart rate and oxygen consumption responses were consistently higher for CAF but failed to reach statistical significance. Individual responses to CAF were labeled positive using a criterion of 13.4 m·min-1 faster for CAF (vs. PLA). Ten of 32 trials (31%) were positive responses. In these, systematic increases were observed for heart rate (∼12 beats·min-1) and oxygen consumption (∼5.7 mL·kg-1·min-1). Blunted/stable respiratory exchange ratio values at higher VEL for positive responders suggest increased free fatty acid reliance during CAF. In conlusion, mean results show a mild effect of CAF during RPE production. However, individual responses more clearly indicate whether a true effect is possible. Trainers and individuals should consider individual responses to ensure effectively intensity regulation.

10.
J Strength Cond Res ; 30(4): 901-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26349041

RESUMO

This study examined the effects of hypohydration on repeated 40-yd sprint performance. Anaerobically fit current and former Division II male athletes (n = 12) completed 2 bouts of 10 × 40-yd sprints followed by an agility test, dehydrated (∼3% body weight [DT]), or hydrated trial (HT). Statistical analysis of group means indicated that hypohydration had little effect on sprint times for either the first (DT= 5.38 ± 0.37; HT = 5.35 ± 0.34) or second (DT = 5.47 ± 0.39; HT = 5.42 ± 0.39) bout of 10 sprints with only sprint number 2, 5, and 6 of bout 2 reaching statistical significance. However, when individual sprint performance was considered, a greater effect was seen. In all, 83% (10 of 12) of subjects experienced a meaningful change (≥0.1 seconds) (positive or negative) in mean sprint time (DT vs. HT) for one or more bout of 10 sprints. Ratings of perceived exertion was significantly higher (∼1 unit on a 10 point scale) for DT in all sprints during bout 1 and the first 2 sprints of bout 2. These results indicate that the effect of hypohydration on repeated sprint performance varies among individuals. Some improved performance with hypohydration, while others experienced detrimental effects. Hypohydration also resulted in a particularly notable negative impact on perceptual measures of exertion even when performance was similar.


Assuntos
Desempenho Atlético/fisiologia , Desidratação/fisiopatologia , Corrida/fisiologia , Adulto , Teste de Esforço , Humanos , Masculino , Esforço Físico , Adulto Jovem
11.
J Sci Med Sport ; 18(5): 569-74, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25154702

RESUMO

OBJECTIVES: Although ergogenic, acute caffeine ingestion may increase urine volume, prompting concerns about fluid balance during exercise and sport events. This meta-analysis evaluated caffeine induced diuresis in adults during rest and exercise. DESIGN: Meta-analysis. METHODS: A search of three databases was completed on November 1, 2013. Only studies that involved healthy adults and provided sufficient information concerning the effect size (ES) of caffeine ingestion on urine volume were included. Sixteen studies met the inclusion criteria, providing a total of 28 ESs for the meta-analysis. Heterogeneity was assessed using a random-effects model. RESULTS: The median caffeine dosage was 300 mg. The overall ES of 0.29 (95% confidence interval (CI) = 0.11-0.48, p = 0.001) corresponds to an increase in urine volume of 109 ± 195 mL or 16.0 ± 19.2% for caffeine ingestion vs. non-caffeine conditions. Subgroup meta-analysis confirmed exercise as a strong moderator: active ES = 0.10, 95% CI = -0.07 to 0.27, p = 0.248 vs. resting ES = 0.54, 95% CI = 0.22-0.85, p = 0.001 (Cochran's Q, p = 0.019). Females (ES = 0.75, 95% CI = 0.38-1.13, p < 0.001) were more susceptible to diuretic effects than males (ES = 0.13, 95% CI = -0.05 to 0.31, p = 0.158) (Cochran's Q, p = 0.003). CONCLUSIONS: Caffeine exerted a minor diuretic effect which was negated by exercise. Concerns regarding unwanted fluid loss associated with caffeine consumption are unwarranted particularly when ingestion precedes exercise.


Assuntos
Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Diurese/efeitos dos fármacos , Exercício Físico , Descanso , Adulto , Feminino , Humanos , Masculino , Modelos Estatísticos , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
12.
J Strength Cond Res ; 28(12): 3425-31, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24875428

RESUMO

Hydration affects multiple aspects of basketball performance, but few investigations have examined the hydration profiles of collegiate basketball players. We examined multiday prepractice hydration status of 11 male and 11 female NCAA (National Collegiate Athletic Association) Division II basketball players' sweat losses, fluid intake, and how accurately players estimated their sweat losses. Urine-specific gravity (USG) was spontaneously assessed before 2 practices. Sweat losses and fluid intakes were measured during a conditioning practice (CP) and sport-specific practice (SP). After practices, players filled 1,030 ml practice bottles to estimate their sweat losses. Urine-specific gravity between practices exhibited a moderate correlation (r = 0.54; p = 0.012) and were consistently high (17% of samples = USG >1.030) with no difference in mean USG between men (1.026 ± 0.004) and women (1.022 ± 0.008). Athletes' estimations of their sweat loss volumes between CP and the longer SP were strongly correlated (r = 0.88; p < 0.001). Estimation error was high (absolute error for both practices = 71 ± 52%) and error direction varied greatly within men. Women consistently underestimated sweat losses by 63 ± 28% and 65 ± 20% during CP and SP. Sweat losses during SP equaled 2,471 ± 495 ml and 1,910 ± 441 ml for men and women, respectively, but high practice fluid intake limited body mass losses to 1.1 ± 0.6% by the end of practice. It is plausible that hypohydration is related to poor conceptualization of sweat losses. Simulating the methodology of this study could help identify chronically hypohydrated athletes and be used to educate on between-practice fluid needs.


Assuntos
Basquetebol/fisiologia , Desidratação/diagnóstico , Sudorese , Adolescente , Desidratação/prevenção & controle , Desidratação/urina , Ingestão de Líquidos , Feminino , Humanos , Masculino , Percepção , Prática Psicológica , Gravidade Específica , Urinálise , Adulto Jovem
13.
J Strength Cond Res ; 28(2): 540-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24476745

RESUMO

Session ratings of perceived exertion (SRPE) during resistance training may be influenced by specific exercise parameters. The purpose of this study was to examine the influence of work rate (total work per unit time) and recording time on SRPE. Participants performed 3 exercise bouts of bench press, lat pull-down, overhead press, upright row, triceps extension, and biceps curl at 60% of predetermined 1 repetition maximum according to these protocols: (a) 3 sets × 8 repetitions (reps) × 1.5 minutes of recovery, (b) 3 sets × 8 reps × 3 minutes of recovery, and (c) 2 sets × 12 reps × 3 minutes of recovery. Session ratings of perceived exertion for the 3 × 8 × 1.5-minute recovery (5.3 ± 1.8) and 2 × 12 × 3-minute recovery trials (6.2 ± 1.7) were significantly greater vs. 3 × 8 × 3-minute recovery trial (4.2 ± 1.8). The difference approached significance between work rate-matched protocols (p = 0.08). No difference was observed between SRPE at 15 minutes (5.1 ± 1.8) vs. 30 minutes (5.2 ± 1.9) post exercise. Post-set in-task ratings of perceived exertion were higher for the 2 × 12 × 3-minute recovery trial (5.9 ± 1.4) vs. 3 × 8 × 1.5-minute recovery trial (4.8 ± 1.2) and 3 × 8 × 3-minute recovery trial (4.0 ± 1.6). The difference approached significance (p = 0.07) for the 3 × 8 × 3-minute recovery trial vs. 3 × 8 × 1.5-minute recovery trial. Session ratings of perceived exertion responded to changes in work rate with no significant difference at matched work rates, indicating that SRPE is responsive to training load. Results indicated that more proximal monitoring (15 minutes post exercise) yielded reliable estimates of SRPE increasing the practical utility of the measure.


Assuntos
Esforço Físico , Treinamento Resistido , Levantamento de Peso/psicologia , Adulto , Frequência Cardíaca , Humanos , Masculino , Percepção , Esforço Físico/fisiologia , Descanso/fisiologia , Descanso/psicologia , Fatores de Tempo , Levantamento de Peso/fisiologia , Adulto Jovem
14.
J Strength Cond Res ; 28(7): 2042-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24378665

RESUMO

Session ratings of perceived exertion (SRPE) are sensitive to changes in total work volume and work rate during resistance training. This study examined the influence of work distribution (varied load, set, and repetitions [reps]) on SRPE in 2 resistance exercise trials matched for total work volume (sets × reps × percentage of 1 repetition maximum [% 1RM]) and work rate (total work volume/time). Participants completed a low load/high rep (LLHR) trial (2 sets × 12 reps × 3-minute recovery at ∼60% 1RM) and a high load/low rep (HLLR) trial (3 sets × 6 reps × 1.5-minute recovery at ∼80% 1RM) of the bench press, lat pull-down, overhead press, upright row, triceps extension, and biceps curl. A 2-minute recovery separated each exercise in both trials. Session ratings of perceived exertion and recovery heart rate (HR) were recorded 20 minutes after exercise. Preset and postset RPE and HR were higher for HLLR vs. LLHR (3.1 ± 1.6; 104 ± 15 b·min-1 vs. 2.1 ± 1.3; 98 ± 10 b·min-1) and (5.5 ± 0.9; 139 ± 14 b·min-1 vs. 4.4 ± 0.9; 131 ± 12 b·min-1), respectively. Session RPE was higher for HLLR (5.7 ± 1.4) vs. LLHR (4.3 ± 1.4) with no difference in recovery HR. Session ratings of perceived exertion was greater with higher load despite matched total volumes and work rates. Higher preset acute RPE and HR in HLLR may indicate differences in recovery between sets. Higher postset acute RPE and HR in HLLR indicated increased difficulty of individual sets in HLLR, which likely contributed to SRPE differences. Practitioners can be confident that SRPE accurately reflects changes in training load when the number of sets, reps, and loads are altered within routine training.


Assuntos
Esforço Físico , Treinamento Resistido/métodos , Levantamento de Peso/psicologia , Adolescente , Adulto , Frequência Cardíaca , Humanos , Masculino , Esforço Físico/fisiologia , Descanso/fisiologia , Descanso/psicologia , Levantamento de Peso/fisiologia , Adulto Jovem
15.
Appl Ergon ; 45(3): 510-4, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23891504

RESUMO

This study examined the separate effects of caffeine and menthol on cognition and mood during simulated firefighting in the heat. Participants (N = 10) performed three trials in a counterbalanced order, either with 400 mg caffeine, menthol lozenges, or placebo. The simulated firefighting consisted of 2 bouts of 20-min treadmill exercise and one bout of 20-min stepping exercise in the heat with two brief 15-min rest periods between each exercise phase. Exercise induced significant dehydration (>3%) and elevated rectal temperature (>38.9 °C), for all three conditions. Neither caffeine nor menthol reduced perceived exertion compared to placebo (p > 0.05). Mood ratings (i.e., alertness, hedonic tone, tension) significantly deteriorated over time (p < 0.05), but there was no difference among the three conditions. Simple reaction time, short-term memory, and retrieval memory did not alter with treatments or repeated evaluations. Reaction accuracy from a math test remained unchanged throughout the experimental period; reaction time from the math test was significantly faster after exposure to the heat (p < 0.05). It is concluded that, exhaustive exercise in the heat severely impacted mood, but minimally impacted cognition. These treatments failed to show ergogenic benefits in a simulated firefighting paradigm in a hot environment.


Assuntos
Afeto/efeitos dos fármacos , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Cognição/efeitos dos fármacos , Bombeiros/psicologia , Temperatura Alta , Mentol/farmacologia , Temperatura Corporal/efeitos dos fármacos , Estudos Cross-Over , Incêndios , Frequência Cardíaca/efeitos dos fármacos , Temperatura Alta/efeitos adversos , Humanos , Masculino , Testes Neuropsicológicos , Esforço Físico/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos , Adulto Jovem
16.
Stud Health Technol Inform ; 192: 866-70, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23920681

RESUMO

We present a new open-source Android application, AccessMRS, for interfacing with an electronic medical record system (OpenMRS) and loading 'Smart Forms' on a mobile device. AccessMRS functions as a patient-centered interface for viewing OpenMRS data; managing patient information in reminders, task lists, and previous encounters; and launching patient-specific 'Smart Forms' for electronic data collection and dissemination of health information. We present AccessMRS in the context of related software applications we developed to serve Community Health Workers, including AccessInfo, AccessAdmin, AccessMaps, and AccessForms. The specific features and design of AccessMRS are detailed in relationship to the requirements that drove development: the workflows of the Kenyan Ministry of Health Community Health Volunteers (CHVs) supported by the AMPATH Primary Health Care Program. Specifically, AccessMRS was designed to improve the quality of community-based Maternal and Child Health services delivered by CHVs in Kosirai Division. AccessMRS is currently in use by more than 80 CHVs in Kenya and undergoing formal assessment of acceptability, effectiveness, and cost.


Assuntos
Registros Eletrônicos de Saúde , Controle de Formulários e Registros/métodos , Armazenamento e Recuperação da Informação/métodos , Registro Médico Coordenado/métodos , Aplicativos Móveis , Linguagens de Programação , Interface Usuário-Computador , Design de Software , Integração de Sistemas
17.
J Strength Cond Res ; 27(10): 2800-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23302757

RESUMO

Session rating of perceived exertion (RPE; SRPE), a convenient model for monitoring the overall perceived exertion of an exercise bout, is not well understood. The SRPE may be linked to final acute RPE before exercise cessation. This study investigated the potential link between terminal acute RPE (TRPE) and the SRPE using cycling trials of equated work. Fifteen subjects (age: 24.3 ± 5.1 years) completed a maximal exertion cycle trial followed by 2 (counterbalanced) 40-minute cycling trials at approximately 75% of individualized V[Combining Dot Above]O2max. By manipulating warm-up and cooldown, the trials were designed to result in a high TRPE (HITRPE) and low TRPE (LOTRPE). The heart rate (HR) and RPE were recorded every 5 minutes during exercise, with the SRPE recorded 20 minutes postexercise. The mean RPE (MeanRPE) during exercise (min 10-40 HITRPE and minutes 5-35 for LOTRPE) was calculated by averaging all RPE responses recorded during exercise at 75% V[Combining Dot Above]O2max. Two-way (trial × time) repeated measures analysis of variance and Bonferroni post hoc tests were used to compare the MeanRPE, SRPE, and TRPE. MeanRPE, HR, and power output (using paired t-test) for exercise at 75% V[Combining Dot Above]O2max did not differ (p > 0.05) between HITRPE and LOTRPE. The TRPE at minute 40 was significantly lower (p < 0.05) for LOTRPE (3.1 ± 2.6) vs. HITRPE (8.2 ± 1.7), no significant difference was found for SRPE (LOTRPE: 7.6 ± 2.0 vs. HITRPE 7.4 ± 1.7). The findings indicate that the SRPE was not linked to TRPE. Further research is warranted using various modalities to extend the understanding of potential mediating factors of SRPE.


Assuntos
Ciclismo/fisiologia , Esforço Físico/fisiologia , Ergometria , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Fatores de Tempo , Adulto Jovem
18.
Res Q Exerc Sport ; 83(2): 282-92, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22808714

RESUMO

This review examines the influence of dehydration on muscular strength and endurance and on single and repeated anaerobic sprint bouts. Describing hydration effects on anaerobic performance is difficult because various exercise modes are dominated by anaerobic energy pathways, but still contain inherent physiological differences. The critical level of water deficit (approximately 3-4%; mode dependent) affecting anaerobic performance is larger than the deficit (approximately 2%) impairing endurance performance. A critical performance-duration component (> 30 s) may also exist. Moderate dehydration (approximately 3% body weight; precise threshold depends on work/recovery ratio) impairs repeated anaerobic bouts, which place an increased demand on aerobic metabolism. Interactions between dehydration level, dehydration mode, testing mode, performance duration, and work/recovery ratio during repeated bouts make the dehydration threshold influencing anaerobic performance mode dependent.


Assuntos
Desidratação/fisiopatologia , Exercício Físico/fisiologia , Restrição Calórica , Metabolismo Energético/fisiologia , Humanos , Força Muscular/fisiologia
19.
Percept Mot Skills ; 112(3): 711-25, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21853760

RESUMO

Eating knowledge, nutritional knowledge, and psychological changes among female collegiate dancers were examined before and after a 4-wk. team-centered program on sport nutrition, exercise, and disordered eating consequences. Collegiate female dancers from two NCAA Division I institutions participated in a control (n = 19; M age = 19.1 yr., SD = 1.0) or intervention (n = 21; M age = 19.2 yr., SD = 1.2) group. Measures were administered to both groups before and after intervention to assess eating disorders, depression, and nutritional and disordered eating knowledge. There was a statistically significant increase in scores on nutritional and overall eating disorder knowledge in the intervention group compared to the control group. Mean scores on depression, drive for thinness, body dissatisfaction, and maturity fears decreased in the intervention group.


Assuntos
Dança/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Processos Grupais , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Serviços de Saúde Escolar , Identificação Social , Adolescente , Imagem Corporal , Mecanismos de Defesa , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Inventário de Personalidade/estatística & dados numéricos , Psicometria , Autoimagem , Adulto Jovem
20.
Percept Mot Skills ; 112(3): 951-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21853781

RESUMO

Knowledge of eating disorders, confidence in knowledge, and attendance of eating disorder educational programs were assessed among NCAA Division I and II university administrators (n = 61), coaches (n = 44), and dancers (n = 53). A questionnaire assessed knowledge in 5 domains: etiology, signs and symptoms, management and treatment, risk factors, and prevention and education. Overall, dancers' knowledge and previous attendance were significantly lower than administrators' and coaches'. There was inconsistency between participants' confidence in answers and the correctness of their answers. Education is necessary for improving knowledge and reducing risky behaviors in auxiliary dancers.


Assuntos
Pessoal Administrativo , Dança/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Educação Física e Treinamento , Instituições Acadêmicas , Esportes/psicologia , Estudantes/psicologia , Adolescente , Imagem Corporal , Feminino , Inquéritos Epidemiológicos , Humanos , Capacitação em Serviço , Magreza/psicologia , Adulto Jovem
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