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1.
Curr Dev Nutr ; 8(9): 104428, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39279784

RESUMO

Background: Dysregulation of adipocyte function occurs in obesity. Meteorin-like protein (Metrnl) is a newly discovered modulator of inflammation, metabolism, and differentiation of human adipocytes. The dietary supplement Chlorella Vulgaris (CV) reduces hyperlipidemia, hyperglycemia, and oxidative stress in clinical trials. Objectives: To explore the impact of 12 wks of interval resistance training (IRT) and CV supplementation on plasma levels of Metrnl and oxidative stress in males with obesity. Methods: Forty-four obese men (BMI: 32.0 ± 1.5 kg/m2, weight: 101.1 ± 2.2 kg, age: 23-35 years) were randomly assigned into 4 groups (n = 11/group): control (CON), CV supplement (CV), IRT, and CV + IRT (CVIRT). The IRT was performed for 12 wks (3 sessions per week). The treatment consisted of a daily intake of CV (1800 mg capsule) or placebo capsules. Blood samples were collected 48 hours before and after the interventions to analyze biomedical measurements. Results: The IRT and CVIRT groups had elevations in plasma Metrnl, superoxide dismutase, and total antioxidant capacity levels (all P < 0.0001), and reductions in malondialdehyde (P < 0.0001). Supplementation with CV significantly reduced malondialdehyde (P < 0.001) and increased total antioxidant capacity (P < 0.0001) but failed to alter superoxide dismutase or Metrnl (P > 0.05). Conclusions: Although IRT and its combination with CV hold promise for improving Metrnl levels and oxidative status in obesity, combining IRT and CV do not yield greater benefits than IRT alone. Although standalone CV supplementation could favorably impact certain markers of oxidative stress, the effectiveness of CV supplementation appears to have a relatively limited effect across assessed biomarkers and requires further investigation.

2.
J Funct Morphol Kinesiol ; 9(3)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39189226

RESUMO

New Zealand blackcurrant (NZBC) is known to alter exercise-induced physiological and metabolic responses with chronic (i.e., 7 days) dosing. We examined the effects of acute intake of New Zealand blackcurrant (NZBC) extract on 4 h indoor cycling-induced physiological and metabolic responses in a male amateur Ironman athlete (age: 49 years; BMI: 24.3 kg·m-2; V˙O2max: 58.6 mL·kg-1·min-1; maximal aerobic power: 400 W; history: 14 Ironman events in 16 years) three weeks before competition. Indirect calorimetry was used and heart rate was recorded at 30 min intervals during 4 h indoor (~22.4 °C, relative humidity: ~55%) constant power (165 W) cycling on a Trek Bontrager connected to a Kickr smart trainer. Blood lactate and rating of perceived exertion (RPE) were taken at 60 min intervals. Study was a single-blind placebo-controlled study with capsules (4 × 105 mg anthocyanins) taken 2 h before starting the 4 h of cycling. Water was allowed ad libitum with personalised consumption of gels [a total of eight with three with caffeine (100 mg)], two bananas and 8 × electrolyte capsules (each 250 mg sodium and 125 mg potassium) at personalised time-points. With NZBC extract (CurraNZ), during 4 h of cycling (mean of 8 measurements), minute ventilation was 8% lower than placebo. In addition, there was no difference for oxygen uptake, with carbon dioxide production found to be 4% lower with NZBC extract. With the NZBC extract, the ventilatory equivalents were lower for oxygen and carbon dioxide by 5.5% and 3.7%; heart rate was lower by 10 beats·min-1; lactate was 40% different with lower lactate at 2, 3 and 4 h; RPE was lower at 2, 3 and 4 h; and carbohydrate oxidation was 11% lower. With NZBC extract, there was a trend for fat oxidation to be higher by 13% (p = 0.096), with the respiratory exchange ratio being lower by 0.02 units. Acute intake of New Zealand blackcurrant extract (420 mg anthocyanins) provided beneficial physiological and metabolic responses during 4 h of indoor constant power cycling in a male amateur Ironman athlete 3 weeks before a competition. Future work is required to address whether acute and chronic dosing strategies with New Zealand blackcurrant provide a nutritional ergogenic effect for Ironman athletes to enhance swimming, cycling and running performance.

3.
J Funct Foods ; 1192024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39036605

RESUMO

Aims: To evaluate the effects of 12-week chlorella vulgaris (CV) combined with interval resistance training (IRT) on plasma levels of leptin, adiponectin and neuregulin-4 (Nrg-4) in obese men. Methods: Obese men (n = 44, BMI of 32.1 ± 1.5 kg/m2) were randomly allocated to the following groups of 11 participants per group: Control Placebo group (CP), CV supplement group (CV), Interval Resistance Training group plus Placebo (IRT + P), and Interval Resistance Training plus CV supplement group (IRT + CV). IRT was performed three times a week for 12 weeks using three sets of 10 repetitions at 60 % 1RM, and integrating an active rest interval with 15 repetitions at 20 % 1RM. Participants consumed either CV (1800 mg daily) or a placebo. Pre- and post-intervention blood samples were obtained to assess adipokines which were measured by ELISA. Results: While CV or IRT separately did not alter plasma levels of leptin (p > 0.05), their combination reduced leptin levels (p = 0.007). IRT and IRT plus CV increased the plasma levels of adiponectin and Nrg-4 (p < 0.01). An intergroup comparison indicated significant elevations of adiponectin and Nrg-4 in the CV compared to the CP group (p < 0.05). Conclusion: The combination of IRT and CV modulates plasma levels of leptin, adiponectin and NRG4 more effectively than either IRT or CV separately in obese men.

4.
J Funct Morphol Kinesiol ; 9(2)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38651434

RESUMO

Four weeks before competition in the 2023 Marathon des Sables, a 6-stage, ~250 km running event in the Sahara Desert, we examined the effects of a 7-day intake of New Zealand blackcurrant extract (210 mg anthocyanins per day) on 1 h treadmill running-induced physiological and metabolic responses in the heat (~34 °C, relative humidity: ~30%) in non-acclimatized amateur female and male athletes (age: 23, 38 yrs, BMI: 24.2, 28.4 kg·m-2, body fat%: 29.2, 18.8%, V˙O2max: 50.1, 52.1 mL·kg-1·min-1). During the 1 h run at 50%V˙O2max (speed female: 7.3, male: 7.5 km·h-1), indirect calorimetry was used, and heart rate was recorded at 15 min intervals with core temperature monitoring (0.05 Hz). The 1 h runs took place 3 h after a light breakfast and 2 h after intake of the final dose of New Zealand blackcurrant extract with water allowed ad libitum during the run. The New Zealand blackcurrant extract had no effects on the female athlete. The respiratory exchange ratio (RER) of the female athlete in the non-supplement control condition was 0.77 ± 0.01, indicating an existing ~77% contribution of fat oxidation to the energy requirements. In the male athlete, during 1 h of running, fat oxidation was higher by 21% (p < 0.01), carbohydrate oxidation was 31% lower (p = 0.05), RER was 0.03 units lower (p = 0.04), and core temperature was 0.4 °C lower (p < 0.01) with no differences for heart rate, minute ventilation, oxygen uptake, and carbon dioxide production for the New Zealand blackcurrant condition compared to the non-supplement control condition. Seven-day intake of New Zealand blackcurrant extract (210 mg anthocyanins per day) provided beneficial physiological and metabolic responses during exertional heat stress by 1 h of indoor (~34 °C) treadmill running in a male Marathon des Sables athlete 4 weeks before competition. Future work is required to address whether New Zealand blackcurrant provides a nutritional ergogenic effect for Marathon des Sables athletes during long-duration running in the heat combined with personalized nutrition.

5.
Eur J Appl Physiol ; 124(8): 2315-2328, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38448730

RESUMO

PURPOSE: To determine if 7d of New Zealand blackcurrant (NZBC) extract alters the heat shock, inflammatory and apoptotic response during prolonged exertional-heat stress. METHODS: Ten men (Age: 29 ± 2 years, Stature: 1.82 ± 0.02 m, Mass: 80.3 ± 2.7 kg, V̇O2max: 56 ± 2 mL·kg-1·min-1) ingested two capsules of CurraNZ™ (NZBC extract: 210 mg anthocyanins·day-1) or PLACEBO for 7d prior to 1 h treadmill run (65% V̇O2max) in hot ambient conditions (34 °C/40% RH). Blood samples were collected before (Pre), immediately after (Post), 1 h after (1-Post), and 4 h after (4-Post) exercise. Heat shock proteins (HSP90, HSP70, HSP32) were measured in plasma. HSP and protein markers of inflammatory capacity (TLR4, NF-κB) and apoptosis (BAX/BCL-2, Caspase 9) were measured in peripheral blood mononuclear cells (PBMC). RESULTS: eHSP32 was elevated at baseline in NZBC(+ 31%; p < 0.001). In PLACEBO HSP32 content in PBMC was elevated at 4-Post(+ 98%; p = 0.002), whereas in NZBC it fell at Post(- 45%; p = 0.030) and 1-Post(- 48%; p = 0.026). eHSP70 was increased at Post in PLACEBO(+ 55.6%, p = 0.001) and NZBC (+ 50.7%, p = 0.010). eHSP90 was increased at Post(+ 77.9%, p < 0.001) and 1-Post(+ 73.2%, p < 0.001) in PLACEBO, with similar increases being shown in NZBC (+ 49.0%, p = 0.006 and + 66.2%, p = 0.001; respectively). TLR4 and NF-κB were both elevated in NZBC at PRE(+ 54%, p = 0.003 and + 57%, p = 0.004; respectively). Main effects of study condition were also shown for BAX/BCL-2(p = 0.025) and Caspase 9 (p = 0.043); both were higher in NZBC. CONCLUSION: 7d of NZBC extract supplementation increased eHSP32 and PBMC HSP32 content. It also increased inflammatory and apoptotic markers in PBMC, suggesting that NZBC supports the putative inflammatory response that accompanies exertional-heat stress.


Assuntos
Apoptose , Exercício Físico , Resposta ao Choque Térmico , Temperatura Alta , Extratos Vegetais , Humanos , Masculino , Extratos Vegetais/farmacologia , Resposta ao Choque Térmico/efeitos dos fármacos , Resposta ao Choque Térmico/fisiologia , Adulto , Exercício Físico/fisiologia , Apoptose/efeitos dos fármacos , Ribes/química , Proteínas de Choque Térmico/metabolismo
6.
Appl Physiol Nutr Metab ; 49(7): 933-942, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502949

RESUMO

To examine the effects of 7-days juçara powder (JP) intake on oxidative stress biomarkers and endurance and sprint cycling performances. In a randomized, placebo-controlled, crossover, and triple-blind study, 20 male trained cyclists were assigned to intake 10 g of JP (240 mg anthocyanins) or placebo (PLA) for 7 days and performed a cycling time-to-exhaustion (TTE). A 5 s cycling sprint was performed before and after the cycling TTE. Blood oxidative stress biomarkers and lactate concentration where evaluated 1 h before (T-1), immediately after (T0), and 1 h after (T1) the cycling TTE. The mean duration time for the cycling TTE was 8.4 ± 6.0% (63 ± 17 s) longer in the JP condition (JP: 751 ± 283 s) compared to PLA (688 ± 266 s) (P < 0.019). Two-way repeated measures Analysis of variance showed an increase in the JP condition for reduced glutathione (GSH) (P = 0.049) at T0 (P = 0.039) and T1 (P = 0.029) compared to PLA with a moderate effect size at T0 (d = 0.61) and T1 (d = 0.57). Blood lactate levels increased over time in both conditions (P ≤ 0.001). No differences were observed for the post-TTE sprint fatigue index, total phenols, protein carbonyls, and glutathione peroxidase activity. Seven-day intake of JP improved cycling endurance performance and increased GSH levels but had no effect on lactate and cycling sprint-induced fatigue.


Assuntos
Desempenho Atlético , Ciclismo , Estudos Cross-Over , Glutationa , Ácido Láctico , Estresse Oxidativo , Resistência Física , Humanos , Masculino , Ciclismo/fisiologia , Glutationa/sangue , Estresse Oxidativo/efeitos dos fármacos , Desempenho Atlético/fisiologia , Adulto , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Ácido Láctico/sangue , Biomarcadores/sangue , Adulto Jovem , Antocianinas/administração & dosagem , Antioxidantes/administração & dosagem , Suplementos Nutricionais
7.
Clin Pract ; 14(1): 327-336, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38391411

RESUMO

Exercise is a recommended part of phase IV cardiovascular rehabilitation (CR). The 1 km treadmill walk test (1-KTWT) is a submaximal continuous exercise test to predict cardiorespiratory fitness in patients with cardiovascular disease. We examined physiological, metabolic and subjective responses in patients with cardiovascular disease with self-selected, unchanging walking speed for two 1-KTWTs. Fifteen men (age: 65 ± 9 yr, height: 174 ± 5 cm, body mass: 86 ± 17 kg, BMI: 28.5 ± 5.5 kg·m-2, body fat%: 27.7 ± 7.5%, 10 on beta-blockers) were recruited from phase IV CR groups in the United Kingdom. Participants established a self-selected walking speed for the 1-KTWT and performed the 1-KTWT on separate days with recording of physiological responses to predict V˙O2peak with equations. For the two 1-KTWTs, no differences existed for walking speed, mean and maximal heart rates, oxygen uptake, predicted V˙O2peak (1st 1-KTWT (range: 41-78% V˙O2peak, 95%CI, 53-65; 2nd 1-KTWT range: 43-78% V˙O2peak, 95%CI, 52-65) and rating of perceived exertion. In phase IV cardiac patients, the 1-KTWT with self-selected, unchanging walking speed can be used for V˙O2peak prediction without the need for a full familiarisation. The self-selected constant walking speed for the first 1-KTWT can be used to support nonsupervised physical activity for phase IV CR patients.

8.
Int J Exerc Sci ; 16(6): 497-512, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37621709

RESUMO

We examined the effects of substitution time (i.e., recovery time) in a simulated field hockey test on physical, technical and perceptual/cognitive performance. Nine sub-elite male field hockey players (age: 20 ± 2 yrs, height: 1.81 ± 0.06 m, body mass: 71 ± 10 kg, body fat: 10.3 ± 3.7%, V̇O2max: 67 ± 3 mL·kg-1·min-1) completed four 8-min 40-s bouts of high-intensity intermittent exercise with 2-min and 5.5-min substitution time replicating the demands of a 4-quarter field hockey match. After each bout, a 15-m maximal sprint, agility/dribbling test, passing accuracy test, and a cognitive task were completed. Heart rate (p < .001) and rating of perceived exertion (RPE) (p < .001) increased with every bout. RPE was higher for the 5.5-min condition during the 2nd and 4th bout. No differences were observed between the substitution times and the number of bouts on 15-m maximal sprint time (2-min: 2.03 ± 0.14 s, 5.5-min: 2.07 ± 0.12 s), average reaction time (2-min: 347.19 ± 30.78 ms, 5.5-min: 346.69 ± 38.73 ms), cognitive error rate (2-min: 0.86 ± 0.77; 5.5-min: 0.44 ± 0.37), passing accuracy (2-min: 6 ± 1, 5.5-min: 6 ± 1) and agility/dribbling time (2-min: 7.06 ± 0.41 s, 5.5-min: 7.23 ± 0.55 s). It was concluded that a longer recovery time (i.e., substitution time 5.5-min) did not provide better physical and technical performance than 2-min during a simulated 4-quarter field hockey test. Further research with a larger sample size should address whether the shorter 2-min substitution time seemed to result in lower cognitive performance.

9.
Sports (Basel) ; 11(5)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37234049

RESUMO

The intake of anthocyanin-rich New Zealand blackcurrant (NZBC) extract (300 mg per day) over a week enhanced 16.1 km cycling time trial (TT) performance in endurance-trained cyclists without acute performance effects. In the present study, the acute effects of an intake of 900 mg of NZBC extract 2 h before performing the 16.1 km cycling TT were examined. A total of 34 cyclists (26 males; 8 females) (age: 38 ± 7 years, V˙O2max: 57 ± 5 mL·kg-1·min-1) completed 4 16.1 km TTs (2 familiarization and 2 experimental trials) over 4 mornings on a home turbo-trainer connected with the online training simulator ZWIFT. There was no difference in time to complete the 16.1 km TT between conditions (placebo: 1422 ± 104 s; NZBC extract: 1414 ± 93 s, p = 0.07). However, when participants were split between faster (<1400 s; 1 female; 16 males) and slower (>1400 s; 7 females; 10 males) cyclists based on average familiarization TTs, a difference in TT performance was observed only in the slower group (placebo: 1499 ± 91 s; NZBC extract: 1479 ± 83 s, p = 0.02). At 12 km (quartile analysis), power output (p = 0.04) and speed (p = 0.04) were higher compared to the placebo with no effects on heart rate and cadence. The acute effects of 900 mg of NZBC extract on a 16.1 km cycling time-trial may depend on the performance ability of male endurance-trained cyclists. More work is needed to address whether there is a sex-specific time-trial effect of NZBC extract independent of performance ability.

10.
Int J Exerc Sci ; 16(6): 193-204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37114115

RESUMO

Cooling the head region during exercise can enhance running performance, but this observation is limited to intermittent cooling. This study investigated the effects of continuous head cooling on 5-km running time-trial (TT) performance in hot conditions. Six male and four female triathletes completed two experimental sessions consisting of two 10-minute runs at 50% and 70% V̇O2max followed by a 5-km TT in the heat (32.0±0.3 °C, 50.1±1.2% RH). In a randomized crossover design, either an ice-filled cooling cap or no cooling cap was provided prior to the 10-minute run at 70%V̇O2max. Performance time, rectal, forehead and mean skin temperature, RPE, thermal comfort, fluid loss, blood lactate and heart rate were recorded. Performance time was faster with a cooling cap (1175±80 s) compared to no cooling cap (1189±76 s, P = 0.034; d = 0.18). The cooling cap reduced forehead temperature (P <0.001) and improved thermal comfort (P = 0.004) but had no effect on any other variable (P > 0.05). Continuously cooling the head with an ice-filled cap enhanced 5-km TT performance in the heat. Participants reported an improved thermal comfort with no change in core temperature. Continuously cooling the head may be a practical strategy to enhance running performance in hot conditions.

11.
Sports (Basel) ; 11(2)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36828320

RESUMO

We examined the game characteristics of badminton and the physiological and metabolic responses in highly trained male junior players. Players from a Badminton England accredited Performance Centre (n = 10, age: 14.0 ± 1.2 y, height: 1.69 ± 0.06 m, body mass: 59.1 ± 5.0 kg) completed a 20-m shuttle run test (V˙O2max: 64 ± 7 mL·kg-1·min-1) and a simulated ability-matched competitive singles badminton game consisting of two 12-min games with a 2-min break wearing the COSMED K5 metabolic system with notational analysis. In five games, 427 points were contested with a rally time of 5.7 ± 3.7 s, a rest time of 11.2 ± 5.9 s, shots per rally of 5.6 ± 3.6, work density of 0.50 ± 0.21, an effective playing time of 32.3 ± 8.4%, and shots frequency of 1.04 ± 0.29. During badminton play, heart rate was 151 ± 12 b·min-1 (82 ± 10% of maximum heart rate), oxygen uptake was 39.2 ± 3.9 mL·kg-1·min-1 (62 ± 7% of V˙O2max), and energy expenditure was 11.2 ± 1.1 kcal·min-1 with a post-game blood lactate of 3.33 ± 0.83 mmol·L-1. Compared to adult badminton play, the physiological responses of junior badminton are lower and may be due to the shorter rally durations. Male junior badminton players should be exposed to training methodologies which include rally durations in excess of what they encounter during match play so as to develop greater consistency. Our observations on game characteristics and physiological responses during junior badminton can be used to inform training practice.

12.
J Sports Med Phys Fitness ; 63(2): 273-281, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35620956

RESUMO

BACKGROUND: We examined the effects of an 8-week modified high-intensity circuit training using body weight as resistance (HICTBW) on health-related physical fitness in sedentary obese women. METHODS: Twenty-four sedentary obese women were allocated into the HICTBW or a non-training control group (CG). The modified HICTBW was performed for eight weeks (three times per week). Training consisted of a 30-second workout and 10-second rest for 12 exercise poses per one circuit (one circuit in the first week), with an increase of one circuit every two weeks. Body weight and body composition included skeletal muscle mass (SMM), body fat mass (BFM), body fat percentage (BF%), visceral fat area (VFA), and skeletal muscle mass to visceral fat area ratio (MFR) were measured. Physical fitness included flexibility of the lower back and hamstrings (FlexLH), and leg and handgrip muscle strength (StrengthLeg, StrengthHG). Cardiovascular endurance included the Åstrand-Rhyming heart rate (HRÅstrand), relative maximum oxygen uptake (relative V̇O2max), and workload. RESULTS: All variables were obtained at baseline, week 4, and week 8. The HICTBW improved FlexLH, StrengthLeg, and relative V̇O2max from baseline to week 4 (All P<0.05). Improvements from baseline to week 8 were observed for SMM, BFM, BF%, VFA and MFR, FlexLH, StrengthLeg, HRÅstrand, relative V̇O2max, and workload (All P<0.05). Furthermore, the HICTBW elicited a higher change in SMM (+2.9%), BFM (-3.4%), BF% (-3.2%), MFR (+9.5%), FlexLH (+145.7%) and relative V̇O2max (+32.3%) than the CG at week-8 (All P<0.05). CONCLUSIONS: An eight-week modified HICTBW program thrice a week is an effective training modality to influence health-related physical fitness in sedentary obese women.


Assuntos
Exercícios em Circuitos , Feminino , Humanos , Força da Mão , Consumo de Oxigênio , Força Muscular/fisiologia , Oxigênio , Aptidão Física/fisiologia , Peso Corporal , Obesidade/terapia , Composição Corporal/fisiologia
13.
J Diet Suppl ; 20(3): 428-443, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34791970

RESUMO

We examined effects of intake duration of New Zealand blackcurrant (NZBC) extract on cardiovascular responses during supine rest and moderate-intensity walking. Recreationally active men (n = 15, age: 24 ± 6 yr, BMI: 24.7 ± 4.3 kg·m-2) volunteered in a randomized, cross-over design. One metabolic equivalent (1-MET) was measured (3.97 ± 0.66 mL·kg-1·min-1) and an incremental walking test was performed to individualize speed at 4 (n = 3) or 5 (n = 12) METs for the 30-min walk (5.7 ± 0.7 km·hr-1). NZBC extract (210 mg of anthocyanins) was taken with breakfast for 7 and 14 days, with a 14-days washout. The final dose was ingested 2-hr before recording of the cardiovascular responses (Portapres Model-2). At rest, %changes at 7- and 14-days intake were observed for stroke volume (+6.8% (trend), p = 0.065; +8.5%, p = 0.012), cardiac output (+10.1%, p = 0.007; +8.5%, p = 0.013), total peripheral resistance (-12.0%, p = 0.004; -13.1%, p = 0.011), diastolic (-5.7%, p = 0.045; -9.7%, p = 0.015) and mean arterial pressure (-4.4%, p = 0.040; -7.2%, p = 0.029), but without intake duration effect. During walking, %changes at 7- and 14-days intake were observed for stroke volume (+7.7% (trend), p = 0.063; +9.9%, p = 0.006), cardiac output (+8.7%, p = 0.037; +10.1%, p = 0.007), diastolic blood pressure (-6.2%, p = 0.042; -10.6%, p = 0.001), and total peripheral resistance (-9.6%, p = 0.042; -13.5%, p = 0.005) but without intake duration effect. During walking, %changes at 14-days were observed only for mean arterial pressure (-6.4%, p = 0.018) and arterio-venous oxygen difference (-7.9%, p = 0.019). NZBC extract affects cardiovascular responses at rest and during moderate-intensity exercise with 7- and 14-day intake. Only during moderate-intensity exercise, a longer intake of NZBC extract was required for an effect on some cardiovascular responses.


Assuntos
Antocianinas , Ribes , Masculino , Humanos , Adolescente , Adulto Jovem , Adulto , Nova Zelândia , Extratos Vegetais/farmacologia , Caminhada , Exercício Físico
14.
J Diet Suppl ; 20(1): 15-27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35404735

RESUMO

Seven-day intake of anthocyanins from New Zealand blackcurrant (NZBC) extract increased cardiac output and femoral artery diameter during a sustained submaximal isometric contraction. It is not known if there are intake duration effects by NZBC extract on the isometric contraction-induced cardiovascular responses. In a repeated measures design, male participants (n = 19, age: 26 ± 4 years) performed a 120-second submaximal (30%) isometric contraction of the knee extensors at baseline and following 1, 4 and 7-days intake of 600 mg·day-1 NZBC extract. During the 120-second submaximal isometric contraction, femoral artery diameter and cardiovascular responses were measured with ultrasound and beat-to-beat hemodynamic monitoring. Femoral artery was larger following 4-days (mean difference = 0.046 cm, 95% CI [0.012, 0.080], p = 0.005) and 7-days (mean difference = 0.078 cm, 95% CI [0.034, 0.123], p < 0.001) in comparison to baseline with no increase with 1-day intake. Systolic and diastolic blood pressure, heart rate and total peripheral resistance were not changed by NZBC extract at 1, 4 and 7-days intake. However, mean arterial pressure, stroke volume, cardiac output and total peripheral resistance were changed at time points during the isometric contraction following 7-days intake in comparison to 1-day intake of NZBC extract (p < 0.05). Alterations in femoral artery diameter and some cardiovascular responses during a submaximal sustained isometric contraction of the knee extensors are affected by the intake duration of New Zealand blackcurrant extract, with no effects by 1-day intake. Our observations suggest that the bioavailability of blackcurrant anthocyanins and anthocyanin-derived metabolites is required for days to alter the mechanisms for isometric-contraction induced cardiovascular responses.


Assuntos
Antocianinas , Ribes , Humanos , Masculino , Adulto Jovem , Adulto , Artéria Femoral , Nova Zelândia , Contração Isométrica , Extratos Vegetais/farmacologia
15.
Int J Exerc Sci ; 16(7): 1191-1204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38287936

RESUMO

We examined the short-term effects of foam rolling (FR), dynamic stretching (DS), and passive rest (PR) following simulated ice hockey exercise (IHE) on heart rate (HR), blood lactate (BL), leg choice reaction time (CRTleg), rating of perceived exertion (RPE), and global rating of change (GRC) in elite ice hockey players. The study followed a randomized cross-over design. Fifteen national male ice hockey players were assigned to the FR, DS, or PR interventions for 10 mins following 35- min of simulated IHE. HR and BL were obtained at 0-, 5- and 10-min post-intervention. CRTleg and RPE were assessed pre-and post-intervention. GRC was evaluated post-intervention. The PR decreased HR faster than the DS at 5-min of post-treatment. Whereas the FR and DS reduced BL levels faster than the PR at 5- and 10-min post-treatment. There was no difference in CRTleg among the FR, DS, and PR. The FR had lower RPE scores compared to the DS and PR post-treatment. As perceptual aspects, the FR was the most preferred treatment by ice hockey athletes. The FR and DS exerted more beneficial effects on BL but not on HR by the passive rest. The FR showed the most effective treatment on the psychological demands by improving RPE and perceptual responses over the DS and PR. Thus, the FR could be used as a choice for post-game recovery treatment on improving physiological and perceptual responses following an intense match-play in ice hockey players.

16.
J Funct Morphol Kinesiol ; 7(4)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36547650

RESUMO

Physical training for ultra-endurance running provides physiological adaptations for exercise-induced substrate oxidation. We examined the effects of New Zealand blackcurrant (NZBC) extract on running-induced metabolic and physiological responses in a male amateur ultra-endurance runner (age: 40 years, body mass: 65.9 kg, BMI: 23.1 kg·m−2, body fat: 14.7%, V˙O2max: 55.3 mL·kg−1·min−1, resting heart rate: 45 beats·min−1, running history: 6 years, marathons: 20, ultra-marathons: 28, weekly training distance: ~80 km, weekly running time: ~9 h). Indirect calorimetry was used and heart rate recorded at 15 min intervals during 120 min of treadmill running (speed: 10.5 km·h−1, 58% V˙O2max) in an environmental chamber (temperature: ~26 °C, relative humidity: ~70%) at baseline and following 7 days intake of NZBC extract (210 mg of anthocyanins·day−1) with constant monitoring of core temperature. The male runner had unlimited access to water and consumed a 100-kcal energy gel at 40- and 80 min during the 120 min run. There were no differences (mean of 8, 15 min measurements) for minute ventilation, oxygen uptake, carbon dioxide production and core temperature. With NZBC extract, the respiratory exchange ratio was 0.02 units lower, carbohydrate oxidation was 11% lower and fat oxidation was 23% higher (control: 0.39 ± 0.08, NZBC extract: 0.48 ± 0.12 g·min−1, p < 0.01). Intake of the energy gel did not abolish the enhanced fat oxidation by NZBC extract. Seven days' intake of New Zealand blackcurrant extract altered exercise-induced substrate oxidation in a male amateur ultra-endurance runner covering a half-marathon distance in 2 h. More studies are required to address whether intake of New Zealand blackcurrant extract provides a nutritional ergogenic effect for ultra-endurance athletes to enhance exercise performance.

17.
Sports (Basel) ; 10(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36287765

RESUMO

Previous studies on performance effects by New Zealand blackcurrant (NZBC) extract used mainly a single exercise task. We examined the effects of NZBC extract in a battery of rugby union-specific tests including speed, agility and strength testing. University male rugby union players (n = 13, age: 21 ± 2 years, height: 182 ± 6 cm, body mass: 87 ± 13 kg) completed two full familiarisations and two experimental visits in an indoor facility. The study had a double blind, placebo-controlled, randomised, crossover design. For the experimental visits, participants consumed NZBC extract (210 mg/day of anthocyanins for 7 days) or placebo with a 7-day wash-out. Testing order was the running-based anaerobic sprint test, the Illinois agility test, seated medicine ball (3 kg) throw, and handgrip strength. With NZBC extract, there may have been an effect for average sprint time to be faster by 1.7% (placebo: 5.947 ± 0.538 s, NZBC extract: 5.846 ± 0.571 s, d = -0.18 (trivial), p = 0.06). However, with NZBC extract there may have been reduced slowing of sprint 2 (d = -0.59 (moderate), p = 0.06) and reduced slowing for sprint 6 (d = -0.56 (moderate), p = 0.03). In the Illinois agility test, there may have also been an effect for the mean time to be faster by 1.6% (placebo: 18.46 ± 1.44 s, NZBC extract: 18.15 ± 1.22 s, d = -0.24 (small), p = 0.07). The correlation between the %change in average sprint time and %change in mean agility time was not significant (Pearson R2 = 0.0698, p = 0.383). There were no differences for the seated medicine ball throw distance (p = 0.106) and handgrip strength (p = 0.709). Intake of NZBC extract in rugby union players seems to improve tasks that require maximal speed and agility but not muscle strength. NZBC blackcurrant extract may be able to enhance exercise performance in team sports that require repeated movements with high intensity and horizontal change of body position without affecting muscle strength.

18.
J Funct Morphol Kinesiol ; 7(2)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35736015

RESUMO

Intake of anthocyanin-rich New Zealand blackcurrant (NZBC) can alter physiological responses that enhance exercise performance. In two studies, we examined the effects of NZBC extract on force steadiness during a sustained submaximal isometric contraction of the quadriceps femoris muscle. With repeated measures designs, male participants in study one (n = 13) and study two (n = 19) performed a 120 s submaximal (30%) isometric contraction of the quadriceps femoris muscle following a 7-day intake of NZBC extract and placebo (study one) and following 0 (control), 1-, 4- and 7-day intake of NZBC extract (study two). Participants for both studies were different. In study one, NZBC extract enhanced isometric force steadiness during the 120 s contraction (placebo: 6.58 ± 2.24%, NZBC extract: 6.05 ± 2.24%, p = 0.003), with differences in the third (60-89 s) and fourth quartile (90-120 s) of the contraction. In study two, isometric force steadiness was not changed following 1 and 4 days but was enhanced following 7-day intake of NZBC extract in comparison to control. In study two, the enhanced isometric force steadiness following 7-day intake did occur in the second (30-59 s), third (60-89 s) and fourth (90-120 s) quartiles. Daily supplementation of anthocyanin-rich NZBC extract can enhance force steadiness of the quadriceps femoris muscle during a sustained submaximal isometric contraction. Our observations may have implications for human tasks that require postural stability.

19.
Front Nutr ; 9: 864323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433792

RESUMO

Dark-colored fruits, especially berries, have abundant presence of the polyphenol anthocyanin which have been show to provide health benefits. Studies with the berry blackcurrant have provided notable observations with application for athletes and physically active individuals. Alterations in exercise-induced substrate oxidation, exercise performance of repeated high-intensity running and cycling time-trial and cardiovascular function at rest and during exercise were observed with intake of New Zealand blackcurrant. The dynamic plasma bioavailability of the blackcurrant anthocyanins and the anthocyanin-derived metabolites must have changed cell function to provide meaningful in-vivo physiological effects. This perspective will reflect on the research studies for obtaining the applied in-vivo effects by intake of anthocyanin-rich supplementation, the issue of individual responses, and the emerging strong potential of anthocyanins for sport and exercise nutrition. Future work with repeated intake of known amount and type of anthocyanins, gut microbiota handling of anthocyanins, and coinciding measurements of plasma anthocyanin and anthocyanin-derived metabolites and in-vivo cell function will be required to inform our understanding for the unique potential of anthocyanins as a nutritional ergogenic aid for delivering meaningful effects for a wide range of athletes and physically active individuals.

20.
Nutrients ; 14(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35406087

RESUMO

New Zealand blackcurrant (NZBC) extract enhanced cycling-induced fat oxidation in female endurance athletes. We examined in recreationally active females the effects of NZBC extract on physiological and metabolic responses by moderate-intensity walking and the relationship of fat oxidation changes with focus on body composition parameters. Twelve females (age: 21 ± 2 y, BMI: 23.6 ± 3.1 kg·m-2) volunteered. Bioelectrical bioimpedance analysis was used for body composition measurements. Resting metabolic equivalent (1-MET) was 3.31 ± 0.66 mL·kg-1·min-1. Participants completed an incremental walking test with oxygen uptake measurements to individualize the treadmill walking speed at 5-MET. In a randomized, double-blind, cross-over design, the 30 min morning walks were in the same phase of each participant's menstrual cycle. No changes by NZBC extract were observed for walking-induced heart rate, minute ventilation, oxygen uptake, and carbon dioxide production. NZBC extract enhanced fat oxidation (10 responders, range: 10-66%). There was a significant correlation for changes in fat oxidation with body mass index; body fat% in legs, arms, and trunk; and a trend with fat oxidation at rest but not with body mass and habitual anthocyanin intake. The NZBC extract responsiveness of walking-induced fat oxidation is body composition-dependent and higher in young-adult females with higher body fat% in legs, arms, and trunk.


Assuntos
Extratos Vegetais , Ribes , Tecido Adiposo/metabolismo , Adulto , Composição Corporal , Feminino , Humanos , Nova Zelândia , Oxirredução , Oxigênio/metabolismo , Consumo de Oxigênio , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Caminhada/fisiologia , Adulto Jovem
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