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1.
J Strength Cond Res ; 30(6): 1597-606, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26479024

RESUMO

Winter weather conditions restrict regular sport-specific endurance training in inline speed skating. As a result, this study was designed to compare the effects of cycling and running training programs on inline speed skaters' endurance performance. Sixteen (8 men, 8 women) high-level athletes (mean ± SD 24 ± 8 years) were randomly assigned to 1 of 2 groups (running and cycling). Both groups trained twice a week for 8 weeks, one group on a treadmill and the other on a cycle ergometer. Training intensity and duration was individually calculated (maximal fat oxidation: ∼52% of V[Combining Dot Above]O2peak: 500 kcal per session). Before and after the training intervention, all athletes performed an incremental specific (inline speed skating) and 1 nonspecific (cycling or running) step test according to the group affiliation. In addition to blood lactate concentration, oxygen uptake (V[Combining Dot Above]O2), ventilatory equivalent (VE/V[Combining Dot Above]O2), respiratory exchange ratio (RER), and heart rate were measured. The specific posttest revealed significantly increased absolute V[Combining Dot Above]O2peak values (2.9 ± 0.4, 3.4 ± 0.7, p = 0.01) and submaximal V[Combining Dot Above]O2 values (p ≤ 0.01). VE/V[Combining Dot Above]O2 and RER significantly decreased at maximal (46.6 ± 6.6, 38.5 ± 3.4, p = 0.005; 1.1 ± 0.03, 1.0 ± 0.04, p = 0.001) and submaximal intensities (p ≤ 0.04). None of the analysis revealed a significant group effect (p ≥ 0.15). The results indicate that both cycling vs. running exercise at ∼52% of V[Combining Dot Above]O2peak had a positive effect on the athletes' endurance performance. The increased submaximal V[Combining Dot Above]O2 values indicate a reduction in athletes' inline speed skating technique. Therefore, athletes would benefit from a focus on technique training in the subsequent period.


Assuntos
Ciclismo/fisiologia , Condicionamento Físico Humano/métodos , Resistência Física/fisiologia , Corrida/fisiologia , Patinação/fisiologia , Adolescente , Adulto , Desempenho Atlético/fisiologia , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Adulto Jovem
2.
J Sports Sci Med ; 15(1): 41-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26957925

RESUMO

The purpose of this study was to compare the effects of running versus cycling training on sprint and endurance capacity in inline speed skating. Sixteen elite athletes (8 male, 8 female, 24 ± 8 yrs) were randomly assigned into 2 training groups performing either 2 session per week of treadmill running or ergometer cycling in addition to 3 skating specific sessions (technique, plyometrics, parkour) for 8 weeks. Training intensity was determined within non-specific (cycling or running) and effects on specific endurance capacity within a specific incremental exercise test. Before and after the intervention all athletes performed a specific (300m) and one non-specific (30s cycling or 200m running) all-out sprint test according to the group affiliation. To determine the accumulation of blood lactate (BLa) and glucose (BGL) 20 µl arterialized blood was drawn at rest, as well as in 1 min intervals for 10 min after the sprint test. The sport-specific peak oxygen uptake (VO2 peak) was significantly increased (+17%; p = 0.01) in both groups and highly correlated with the sprint performance (r = -0.71). BLa values decreased significantly (-18%, p = 0.02) after the specific sprint test from pre to post-testing without any group effect. However, BGL values only showed a significant decrease (-2%, p = 0.04) in the running group. The close relationship between aerobic capacity and sprint performance in inline speed skating highlights the positive effects of endurance training. Although both training programs were equally effective in improving endurance and sprint capacities, the metabolic results indicate a faster recovery after high intensity efforts for all athletes, as well as a higher reliance on the fat metabolism for athletes who trained in the running group. Key pointsIn addition to a highly developed aerobic performance inline speed skaters also require a highly trained anaerobic capacity to be effective in the sprint sections such as the mass start, tactical attacks and finish line sprint.An 8-week low-intensity endurance training program of either cycling or running training combined with additional routine training improves classical aerobic characteristics (17% increase of VO2 peak), as well as values for acceleration and speed.Athletes who trained in the running group demonstrated a higher reliance on the fat metabolism in the sport-specific post-testing.The significant reduction in anaerobic ATP turnover during repeated sprints appears to be partially compensated by an increase in VO2 in subsequent sprint. The results revealed a close relationship between the aerobic capacity and sprint performance in inline speed skating.

3.
Eur J Pain ; 24(3): 568-579, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31738468

RESUMO

BACKGROUND: The phenomenon of exercise-induced hypoalgesia and concomitant mood changes is well-established. How exercise-induced hypoalgesia and affective responses are shaped by the intensity of an acute exercise bout and individual fitness levels is as yet not well-understood. This study investigates whether heat pain threshold (PTh), pain tolerance (PTol) and affective parameters are modulated by the intensity of an acute exercise bout and/or individuals' fitness level. Stronger analgesic responses are hypothesized after high-intensity exercise in physically fitter subjects, possibly in sync with concomitant mood changes. METHODS: Thirty-three healthy men were recruited (sedentary: N = 17 or recreational: N = 14; mean age: 25.3 ± 4.4 years). After a fitness assessment on a cycle ergometer, subjects underwent three experimental conditions on separate days: high (20 min exercise 20% above lactate threshold), low (20 min exercise 20% below lactate threshold) and control (seated rest). Before and after each intervention Positive and Negative Affect Schedule, PTh and PTol (cold water emersion test) were assessed. RESULTS: Results indicate an increase of the Positive Affect Scale (high: 26.7 ± 9.0 vs. 32.9 ± 7.1, p < .001; low: 26.3 ± 7.2 vs. 32.0 ± 7.0, p < .001) and PTh (high: 45.1 ± 3.1°C vs. 46.0 ± 2.6°C, p = .003; low: 45.4 ± 2.7°C vs. 45.9 ± 2.6°C, p = .012) after both exercise conditions. In an exploratory analysis, PTol significantly increased only after the high exercise condition (51.2 ± 33.7 s vs. 72.4 ± 64.0 s, p = .045). Fitness level was positively correlated with the increase in PTol from pre to post high-intensity exercise (r = .59, p (one-tailed) = .002). CONCLUSION: Exercise-induced hypoalgesia depends on exercise intensity and appears to be influenced by individual fitness status, independent of mood responses. SIGNIFICANCE: Antinociceptive effects can be elicited by physical exercise and have been extensively investigated in the literature. However, the relation between exercise intensity, fitness status, and the degree of antinociception is not well-understood. This randomized intervention provides novel evidence that antinociceptive effects indeed depend on exercise intensity, but also on general fitness status. Data extend the existing literature by highlighting aspects of exercise behaviour that promote antinociception. Effects do not simply mirror positive affective responses induced by exercise, hence, indicating partially distinct underlying mechanisms.


Assuntos
Afeto , Exercício Físico , Adulto , Humanos , Ácido Láctico , Masculino , Dor , Limiar da Dor , Aptidão Física , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-32961848

RESUMO

Background: An important motivation for adolescents and young adults to engage in aerobic exercise (AE) is to improve fitness, body composition and physical appearance. These parameters have an impact on bodily perception as conceptualized by the 'body image' (BI) construct. AE is known to have positive effects on pain perception, mood, and body image (BI). However, no study has hitherto investigated their interrelationship within one study. Methods: Participants were randomly assigned to an intervention group (IG, n = 16, 6 months of AE) or a passive control group (CG, n = 10). Frankfurt Body-Concept Scales (FKKS), Positive and Negative Affect Scale (PANAS), State and Trait Anxiety Inventory, warmth and heat pain thresholds (WPT, HPT), pain tolerance, and graded exercise test data from baseline (T0) and the end of the intervention (T6) were analyzed using a paired t-test (p < 0.05). Results: A significant increase in the BI dimension 'physical efficacy' was identified from T0 to T6, which correlated positively with PANAS Positive Affect Scale and HPT. Conclusion: Data in young adults undergoing AE indicate that changes in the BI sub-category 'physical efficacy' are closely linked with changes in positive affect and antinociception. These novel findings suggest that BI plays a role in antinociception and positive affect.


Assuntos
Afeto , Imagem Corporal , Terapia por Exercício , Percepção da Dor , Adolescente , Composição Corporal , Exercício Físico , Humanos , Adulto Jovem
5.
Front Physiol ; 10: 1054, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31611803

RESUMO

BACKGROUND: Endurance capacity is one of the main performance determinants in handcycling. There are two exercise test procedures primarily applied to determine endurance capacity, to verify training adaptations and predict race performance. This study aims to evaluate the agreement of these applied concepts in handcycling. METHODS: In a repeated measures cross-over design, 11 highly trained male spinal cord injured (Th12 to L1) handcyclists (age: 40 ± 9 years, height: 183 ± 8 cm, body mass: 73.2 ± 8.5 kg) performed a graded exercise test (GXT) and a lactate minimum test (LMT) to determine lactate threshold at 4 mmol L-1 (LT4 mmol L-1) and lactate minimum (LM), respectively. The agreement of both lactate thresholds concepts for constant load performance prediction (change of ≤ 1 mmol L-1 during the last 20 min) was evaluated within constant load tests (CLT; 30 min) at a power output (PO) corresponding to LT4 mmol L - 1 and LM. Oxygen uptake ( V . ⁢ O 2 ), respiratory exchange ratio (RER), heart rate (HR) and blood lactate (La) were measured during all tests. RESULTS: Power output at the corresponding thresholds (LT4 mmol L-1: 149 ± 34 W vs. LM: 137 ± 18 W) revealed no significant difference (p = 0.06). During the CLT at LT4 mmol ⋅ L -1 and LM, V . ⁢ O 2 , and RPE were not significantly different. However, LA, RER, and HR were significantly higher (p ≤ 0.02) during CLT at LT4 mmol L-1. Bland-Altman plots indicate a wide range of dispersion for all parameters between both lactate threshold concepts. Evaluations of LT4 mmol L-1 and LM did not meet the criteria for constant load performance within the CLT for 33 and 17% of the athletes, respectively. DISCUSSION: Both exercise tests and the corresponding lactate threshold concept revealed appropriate estimates to predict a steady state performance for the majority of participants. However, as PO determination at LT4 mmol L-1 and LM exceeds the criteria for constant load performance (increase of ≥ 1 mmol L-1) for 33 and 17% respectively the current results indicate the common criteria for constant load performance (change of ± 1 mmol L-1) might not be sufficiently precise for elite athletes in handcycling. Consequently, exercise test results of elite athletes should be analyzed individually and verified by means of several CLT.

6.
Eur J Sport Sci ; 18(3): 397-406, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29343183

RESUMO

This study investigated protein kinase activation and gene expression of angiogenic factors in response to low-load resistance exercise with or without blood flow restriction (BFR). In a repeated measures cross-over design, six males performed four sets of bilateral knee extension exercise at 20% 1RM (reps per set = 30:15:15:continued to fatigue) with BFR (110 mmHg) and without (CON). Muscle biopsies were obtained from the vastus lateralis before, 2 and 4 h post-exercise. mRNA expression was determined using real-time RT-PCR. Protein phosphorylation/expression was determined using Western blot. p38MAPK phosphorylation was greater (p = 0.05) at 2 h following BFR (1.3 ± 0.8) compared to CON (0.4 ± 0.3). AMPK phosphorylation remained unchanged. PGC-1α mRNA expression increased at 2 h (5.9 ± 1.3 vs. 2.1 ± 0.8; p = 0.03) and 4 h (3.2 ± 0.8 vs. 1.5 ± 0.4; p = 0.03) following BFR exercise with no change in CON. PGC-1α protein expression did not change following either exercise. BFR exercise enhanced mRNA expression of vascular endothelial growth factor (VEGF) at 2 h (5.2 ± 2.8 vs 1.7 ± 1.1; p = .02) and 4 h (6.8 ± 4.9 vs. 2.5 ± 2.7; p = .01) compared to CON. mRNA expression of VEGF-R2 and hypoxia-inducible factor 1α increased following BFR exercise but only eNOS were enhanced relative to CON. Matrix metalloproteinase-9 mRNA expression was not altered in response to either exercise. Acute low-load resistance exercise with BFR provides a targeted angiogenic response potentially mediated through enhanced ischaemic and shear stress stimuli.


Assuntos
Exercício Físico/fisiologia , Neovascularização Fisiológica , Proteínas Quinases/metabolismo , Músculo Quadríceps/fisiologia , Treinamento Resistido , Adulto , Estudos Cross-Over , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fluxo Sanguíneo Regional , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto Jovem , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
J Sports Med Phys Fitness ; 56(9): 1007-12, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26745782

RESUMO

This study was designed to investigate the intensity profile during an inline speed skating marathon road race. A highly-trained male athlete (20 y, 73.4 kg, 178 cm, V̇O2 peak: 60.8 mL·kg-1·min-1) participated in a marathon road race. Oxygen uptake (V̇O2), respiratory exchange ratio (RER), heart rate (HR) and speed were measured using a portable gas analysis system with a HR monitor and GPS-Sensor integrated. The athlete´s peak V̇O2, HR and speed at ventilatory thresholds were assessed during an incremental field test (22 km·h-1, increase 2 km·h-1 every 5 min) one week before the race. During the race, the absolute time spent in the "easy intensity zone" (V̇O2 below VT1) was 1 min, 49 min "moderate intensity zone" (V̇O2 between VT1 and VT2), and 26 min in the "hard intensity zone" (V̇O2 above VT2). The average HR was 171±6 bpm, corresponding to 95% of the maximum. This study shows that inline speed skating road races over a marathon are conducted at moderate to high V̇O2 and heart rate levels. The physiological racing pattern is very intermittent, requiring both a high level of aerobic and anaerobic capacity.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Patinação/fisiologia , Adulto , Atletas , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
8.
J Sports Med Phys Fitness ; 56(4): 406-14, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25422870

RESUMO

BACKGROUND: The most effective way to measure exercise performance in inline speed skating (ISS) has yet to be established. Generally most athletes are examined by means of traditional but unspecific cycling (CYC) or running (RUN) testing. The present study investigates whether a sport-specific incremental test in ISS reveals different results. METHODS: Eight male top level inline speed skaters (age: 30±4 years; 65.4±6.3 mL∙kg-1∙min-1, training: 12-14 h/week) performed three incremental exhaustive tests in a randomized order (ergometer CYC, field RUN, field ISS). During the tests, heart rate (HR), oxygen uptake (V̇O2, energy expenditure (EE) and blood lactate concentration (BLC) were measured. RESULTS: Analysis of variance revealed no significant differences for peak HR (187±9, 191±9, 190±9; P=0.75), BLC (10.9±2.3, 10.8±2.4, 8.5±3.2; P=0.25), V̇O2 (65.4±6.3, 66.8±3.5, 66.4±6.5; P=0.91) and EE (1371±165, 1335±93, 1439±196; P=0.51) between ISS and CYC or RUN test. Similar results appeared for HR and V̇O2 at submaximal intensities (2 and 4 mmol·L-1 BLC; P≥0.05). Small to moderate effect sizes 0.3-0.87 and considerable variability of differences between the exercise modes (mean bias range between 1% and 17% with 95% limits of agreement between 3% and 33%) among submaximal and maximal results limit the comparability of the three tests. CONCLUSIONS: Consequently, CYC and RUN tests may be considered as qualified alternatives for a challenging ISS test. However a sport-specific test should be conducted in cases of doubt, or when precision is required (e.g. for elite athletes or scientific studies).


Assuntos
Atletas , Teste de Esforço/métodos , Patinação/fisiologia , Adulto , Desempenho Atlético/fisiologia , Metabolismo Energético , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
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