The Relationship between Resistance Exercise Performance and Ventilatory Efficiency after Beetroot Juice Intake in Well-Trained Athletes

The assessment of ventilatory efficiency is critical to understanding the matching of ventilation (VE) and perfusion in the lungs during exercise. This study aimed to establish a causal physiological relationship between ventilatory efficiency and resistance exercise performance after beetroot juice (BJ) intake. Eleven well-trained males performed a resistance exercise test after drinking 140 mL of BJ (~12.8 mmol NO3−) or a placebo (PL). Ventilatory efficiency was assessed by the VE•VCO2−1 slope, the oxygen uptake efficiency slope and the partial pressure of end-tidal carbon dioxide (PetCO2). The two experimental conditions were controlled using a randomized, double-blind crossover design. The resistance exercise test involved repeating the same routine twice, which consisted of wall ball shots plus a full squat (FS) with a 3 min rest or without a rest between the two exercises. A higher weight lifted was detected in the FS exercise after BJ intake compared with the PL during the first routine (p = 0.004). BJ improved the VE•VCO2−1 slope and the PetCO2 during the FS exercise in the first routine and at rest (p < 0.05). BJ intake improved the VE•VCO2−1 slope and the PetCO2 coinciding with the resistance exercise performance. The ergogenic effect of BJ could be induced under aerobic conditions at rest.

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Carbohydrate mouth rinsing improves resistance training session performance

International Journal of Sports Science & Coaching ◽

10.1177/1747954118755640 ◽

2018 ◽

Vol 13 (5) ◽

pp. 804-809 ◽

Cited By ~ 3

Author(s):

Luciana S Decimoni ◽

Victor M Curty ◽

Livia Almeida ◽

Alexander J Koch ◽

Jeffrey M Willardson ◽

...

Keyword(s):

Resistance Exercise ◽

Exercise Performance ◽

Repeated Measures ◽

Perceived Exertion ◽

Bench Press ◽

Statistical Significance ◽

Training Session ◽

Rating Of Perceived Exertion ◽

Double Blind ◽

Mouth Rinsing

We investigated the effect of carbohydrate mouth rinsing on resistance exercise performance. Fifteen recreationally trained women (age 26 ± 4 y; height 1.61.9 ± 5.1 m; weight 59.5 ± 8.2 kg) completed two resistance exercise bouts consisting of three sets of five exercises (half-squat, leg press, bench press, military press, and seated row) to volitional fatigue with a 10 repetition-maximum load. Immediately prior to and during the middle of each exercise bout, subjects mouth rinsed for 10 s with 100 mL of either a 6% maltodextrin solution (CHO) or an artificially flavored solution (PLA) in a randomized, double-blind, counterbalanced fashion. Heart rate and perceived exertion were compared between conditions using a 2 (conditions) × 15 (time points) repeated measures ANOVA. Significant main effects were further analyzed using pairwise comparisons with Bonferroni post hoc tests. Total volume (exercises * sets * repetitions * load) between sessions was compared with a Student’s t-test. Statistical significance was set at p ≤ 0.05 level of confidence. The CHO resulted in more repetitions performed during half-squat, bench press, military press, and seated row, for a significantly greater (∼12%) total volume load lifted versus PLA ( p = 0.039, ES: 0.49). Rating of perceived exertion was also significantly lower in the CHO versus PLA ( p = 0.020, ES: 0.28). These data indicate that CHO mouth rinsing can enhance high-volume resistance exercise performance and lower ratings of perceived exertion.

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Opposite actions of caffeine and creatine on muscle relaxation time in humans

Journal of Applied Physiology ◽

10.1152/japplphysiol.00255.2001 ◽

2002 ◽

Vol 92 (2) ◽

pp. 513-518 ◽

Cited By ~ 40

Author(s):

P. Hespel ◽

B. Op ‘t Eijnde ◽

M. Van Leemputte

Keyword(s):

Relaxation Time ◽

Exercise Test ◽

Muscle Relaxation ◽

Creatine Supplementation ◽

Caffeine Intake ◽

Short Term ◽

Experimental Conditions ◽

Double Blind ◽

Musculus Quadriceps ◽

Intermittent Contractions

The effect of creatine and caffeine supplementation on muscle torque generation and relaxation was investigated in healthy male volunteers. Maximal torque (Tmax), contraction time (CT) from 0.25 to 0.75 of Tmax, and relaxation time (RT) from 0.75 to 0.25 of Tmax were measured during an exercise test consisting of 30 intermittent contractions of musculus quadriceps (2 s stimulation, 2 s rest) that were induced by electrical stimulation. According to a double-blind randomized crossover design, subjects ( n = 10) performed the exercise test before (pretest) and after (posttest) creatine supplementation (Cr, 4 × 5 g/day, 4 days), short-term caffeine intake (Caf, 5 mg · kg−1 · day−1, 3 days), creatine supplementation + short-term caffeine intake (Cr+Caf), acute caffeine intake (ACaf, 5 mg/kg) or placebo. Compared with placebo, Cr shortened RT by ∼5% ( P < 0.05). Conversely, Caf increased RT (+∼10%, P < 0.05), in particular as RT increased because of fatigue. RT was not significantly changed by either Cr+Caf or ACaf. Tmax and CT were similar during all experimental conditions. Initial Tmax was ∼20% of voluntary maximal isometric contraction force, which was not different between treatments. It is concluded that Caf intake (3 days) prolongs muscle RT and by this action overrides the shortening of RT due to creatine supplementation.

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Pre-Sleep Consumption of Casein and Whey Protein: Effects on Morning Metabolism and Resistance Exercise Performance in Active Women

Nutrients ◽

10.3390/nu10091273 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1273 ◽

Cited By ~ 6

Author(s):

Takudzwa Madzima ◽

Jared Melanson ◽

Jonas Black ◽

Svetlana Nepocatych

Keyword(s):

Resistance Exercise ◽

Indirect Calorimetry ◽

Exercise Performance ◽

Resting Metabolic Rate ◽

Milk Proteins ◽

Double Blind ◽

Repetition Maximum ◽

Volume Weight ◽

Blind Crossover Study ◽

Double Blind Crossover Study

Consuming milk proteins (casein (CP) and whey (WP)) at night before sleep has been shown to positively influence next morning resting metabolic rate (RMR). No data exist regarding the effect of pre-sleep consumption of CP and WP on the ability to perform resistance exercise (RE) the following morning. The present study compared the effects of low (24 g) and high (48 g) doses of CP and WP and a non-energetic placebo (PLA) consumed 30 min before sleep on morning RMR, and RE performance. Nine active women participated in this randomized, double-blind, crossover study. Next morning RMR was measured via indirect calorimetry. RE was performed on six machines for 2 sets of 10 repetitions, and a 3rd set to failure at 60% of one-repetition maximum to calculate RE volume (weight lifted × sets × repetitions). Magnitude based inferences were used. Compared to the PLA, 48 g CP had a likely increase in RMR (4.0 ± 4.8%) and possibly trivial (1.1 ± 7.0%) effect on RE volume. There were no clear effects of 24 g CP, 24 g and 48 g of WP on RMR and RE volume. In conclusion, 48 g CP elicited favorable changes in morning RMR, with only trivial changes in RE performance.

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Arterial [H+] and the ventilatory response to hypoxia in humans: influence of acetazolamide-induced metabolic acidosis

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00255.2009 ◽

2010 ◽

Vol 298 (1) ◽

pp. L89-L95 ◽

Cited By ~ 22

Author(s):

Luc J. Teppema ◽

Eveline L. A. van Dorp ◽

Albert Dahan

Keyword(s):

Metabolic Acidosis ◽

Oxygen Saturation ◽

Inhibitory Effect ◽

Saturation Curve ◽

Double Blind ◽

Hypoxic Response ◽

Leftward Shift ◽

End Tidal ◽

Response Line ◽

The Relationship

In this study, we investigated possible separate effects of H+ ions and CO2 on hypoxic sensitivity in humans. We also examined whether hypoxic sensitivity, conventionally defined as the ratio of (hypoxic − normoxic) ventilation over (hypoxic − normoxic) Hb oxygen saturation can also be estimated by taking the ratio (hypoxic − normoxic) ventilation over (logPaO2 hypoxia − logPaO2 normoxia), enabling one to measure the hypoxic response independently from potential confounding influences of changes in position of the Hb oxygen saturation curve. We used acetazolamide to induce a metabolic acidosis. To determine the acute hypoxic response (AHR), we performed step decreases in end-tidal Po2 to ∼50 Torr lasting 5 min each at three different constant end-tidal Pco2 levels. Nine subjects ingested 250 mg of acetazolamide or placebo every 8 h for 3 days in a randomized double-blind crossover design. The metabolic acidosis was accompanied by a rise in ventilation, a substantial fall in PaCO2, and a parallel leftward shift of the ventilatory CO2 response curve. In placebo, CO2 induced equal relative increases in hypoxic sensitivity (O2-CO2 interaction) regardless of the way it was defined. Acetazolamide shifted the response line representing the relationship between hypoxic sensitivity and arterial [H+] ([H+]a) to higher values of [H+]a without altering its slope, indicating that it did not affect the O2-CO2 interaction. So, in contrast to an earlier belief, CO2 and H+ have separate effects on hypoxic sensitivity. This was also supported by the finding that infusion of bicarbonate caused a leftward shift of the hypoxic sensitivity-[H+]a response lines in placebo and acetazolamide. A specific inhibitory effect of acetazolamide on hypoxic sensitivity was not demonstrated.

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Relationship of hypoxic ventilatory response to exercise performance on Mount Everest

Journal of Applied Physiology ◽

10.1152/jappl.1984.56.6.1478 ◽

1984 ◽

Vol 56 (6) ◽

pp. 1478-1483 ◽

Cited By ~ 95

Author(s):

R. B. Schoene ◽

S. Lahiri ◽

P. H. Hackett ◽

R. M. Peters ◽

J. S. Milledge ◽

...

Keyword(s):

High Altitude ◽

Sea Level ◽

Exercise Performance ◽

Ventilatory Response ◽

Hypoxic Ventilatory Response ◽

Maximum Exercise ◽

Exercise Ventilation ◽

End Tidal ◽

Relationship Of ◽

The Relationship

At very high altitude, exercise performance in the human sojourner may depend on a sufficient hypoxic ventilatory response (HVR). To study the relationship of HVR to exercise performance at high altitude, we studied HVR at sea level and 5,400 m and exercise ventilation at sea level, 5,400 m, and 6,300 m in nine members of the American Medical Research Expedition to Everest. The relationship of HVR between individuals was maintained when HVR was repeated after acclimatization to 5,400 m (P less than 0.05). There was a significant correlation in all subjects between HVR and ventilatory equivalent during exercise at sea level (r = 0.704, P less than 0.05). Subjects were then grouped into high (H) and low (L) HVR responders (ventilation increase to end-tidal PO2 of 40 Torr = 21.2 +/- 5.4 and 5.6 +/- 0.9 1 X min-1, respectively. At low and moderate levels of exercise, ventilation at sea level and after acclimatization to 6,300 m was higher in the high HVR group. At 6,300 m blood O2 saturation (Sao2%) decreased from rest to maximum exercise: H = 8.3 +/- 1.8%, L = 20.0 +/- 2.5% (P less than 0.01). HVR correlated inversely in all subjects with the decrease in Sao2 from rest to maximum exercise (P less than 0.05). Climbers with the highest HVR values reached and slept at higher altitudes. We conclude that the relative value of HVR in our group of climbers was not significantly altered after acclimatization; HVR predicts exercise ventilation at sea level and high altitude; the drop in Sao2% that occurs with exercise is inversely related to HVR; and sojourners with high HVR may perform better at extreme altitude.

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Effects Of Caffeine, Beetroot Juice And Its Interaction Consumption On Exercise-Related Fatigue

Kinesiology ◽

10.26582/k.53.2.1 ◽

2021 ◽

Vol 53 (2) ◽

pp. 185-192

Author(s):

Daniel Castillo ◽

Alejandro Rodríguez-Fernández ◽

Rodrigo Ramirez-Campillo ◽

Javier Raya-González

Keyword(s):

Beetroot Juice ◽

Mean Power ◽

Experimental Conditions ◽

Placebo Condition ◽

Double Blind ◽

Performance Reduction ◽

Significant Performance ◽

And Performance ◽

Double Blind Design ◽

Mean Power Output

The aim of this study was to analyze the effect of different supplementation conditions on fatigue and performance in flywheel half-squat tests in senior men. Sixteen active males (age: 22.8±4.9 years; body mass index: 23.7±2.4 kgm-2) participated in the intervention during a 4-week period. Four experimental conditions were established using a double-blind design: placebo, caffeine (CAF), beetroot juice (BRJ), and combined BRJ+CAF. To assess the effect of supplementation, participants completed a countermovement jump (CMJ) before (Pre), 30 s after (Post-30s) and 180 s after (Post-180 s) completing a flywheel half-squat exercise protocol (four sets of eight all-out repetitions, with 3-min inter-set rest, using different inertial loads). Additionally, the mean power output during the flywheel half-squat protocol was recorded. Repeated measured ANOVA showed greater mean power (~1000 W, p<.001) produced/OR/generated in flywheel exercise after the CAF, BRJ and BRJ+CAF consumption compared to the placebo condition. After placebo, CAF and BRJ, CMJ performance at Post-180 s was reduced compared to Pre (p=.003-.087, two-way ANOVA; ES=-0.39/-0.49), although no significant performance reduction (p=.087) was noted after BRJ+CAF. In conclusion, compared to placebo, CAF, BRJ and BRJ+CAF allow greater total mean power in the flywheel half-squat power test, although without effects on exercise-related fatigue. Additionally, BRJ+CAF improved recovery after a high demanding power-production protocol.

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Evaluation of the Efficacy of ST2 and NT-proBNP in the Diagnosis and Prediction of Short- Term Prognosis in Heart Failure with Reduced Ejection Fraction

International Journal of Pharmaceutical and Clinical Research ◽

10.25258/ijpcr.v9i04.8539 ◽

2017 ◽

Vol 9 (04) ◽

Author(s):

Shivananda B Nayak ◽

Dharindra Sawh ◽

Brandon Scott ◽

Vestra Sears ◽

Kareshma Seebalack ◽

...

Keyword(s):

Heart Failure ◽

Ejection Fraction ◽

Cardiac Biomarkers ◽

Double Blind Study ◽

Short Term ◽

Double Blind ◽

Reduced Ejection Fraction ◽

The Mean ◽

Design And Methods ◽

The Relationship

Purpose: i) To determine the relationship between the cardiac biomarkers ST2 and NT-proBNP with ejection fraction (EF) in heart failure (HF) patients. ii) Assess whether a superiority existed between the aforementioned cardiac markers in diagnosing the HF with reduced EF. iii) Determine the efficacy of both biomarkers in predicting a 30-day cardiovascular event and rehospitalization in patients with HF with reduced EF iv) To assess the influence of age, gender, BMI, anaemia and renal failure on the ST2 and NT-proBNP levels. Design and Methods: A prospective double-blind study was conducted to obtain data from a sample of 64 cardiology patients. A blood sample was collected to test for ST2 and NT-proBNP. An echocardiogram (to obtain EF value), electrocardiogram and questionnaire were also obtained. Results: Of the 64 patients enrolled, 59.4% of the population had an EF less than 40%. At the end of the 30- day period, 7 patients were warded, 37 were not warded, one died and 17 were non respondent. Both biomarkers were efficacious at diagnosing HF with a reduced EF. However, neither of them were efficacious in predicting 30-day rehospitalization. The mean NT-proBNP values being: not rehospitalized (2114.7486) and 30 day rehospitalization (1008.42860) and the mean ST2 values being: not rehospitalized (336.1975), and 30-day rehospitalization. (281.9657). Conclusion: Neither ST2 or NT-proBNP was efficacious in predicting the short- term prognosis in HF with reduced EF. Both however were successful at confirming the diagnosis of HF in HF patients with reduced EF.

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The Acute Effects of Androstenedione Supplementation in Healthy Young Males

Canadian Journal of Applied Physiology ◽

10.1139/h00-005 ◽

2000 ◽

Vol 25 (1) ◽

pp. 68-78 ◽

Cited By ~ 34

Author(s):

Craig S. Ballantyne ◽

Stuart M. Phillips ◽

Jay R. Macdonald ◽

Mark A. Tarnopolsky ◽

J. Duncan Macdougall

Keyword(s):

Luteinizing Hormone ◽

Resistance Exercise ◽

Elevated Plasma ◽

Acute Effects ◽

Double Blind ◽

Male Athletes ◽

Young Males ◽

Plasma Estradiol ◽

Key Words Testosterone ◽

Heavy Resistance Exercise

We examined the effects of androstenedione supplementation on the hormonal profile of 10 males and its interaction with resistance exercise. Baseline testosterone, luteinizing hormone, estradiol, and androstenedione concentrations were established by venous sampling at 3 hr intervals over 24 hr. Subjects ingested 200 mg of androstenedione daily for 2 days, with second and third day blood samples. Two weeks later, they ingested androstenedione or a placebo for 2 days, in a double-blind, cross-over design. On day 2, they performed heavy resistance exercise with blood sampled before, after, and 90 min post. The supplement elevated plasma androstenedione 2-3-fold and luteinizing hormone ∼70% but did not alter testosterone concentration. Exercise elevated testosterone, with no difference between conditions. Exercise in the supplemented condition significantly elevated plasma estradiol by ∼83% for 90 min. Androstenedione supplementation, thus, is unlikely to provide male athletes with any anabolic benefit and, with heavy resistance exercise, elevates estrogen. Key Words: testosterone, luteinizing hormone, estradiol, fluid shifts, resistance exercise

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Single Ingestion of Trehalose Enhances Prolonged Exercise Performance by Effective Use of Glucose and Lipid in Healthy Men

Nutrients ◽

10.3390/nu13051439 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1439

Author(s):

Naomi Hamada ◽

Tsuyoshi Wadazumi ◽

Yoko Hirata ◽

Mayumi Kuriyama ◽

Kanji Watanabe ◽

...

Keyword(s):

Exercise Performance ◽

Prolonged Exercise ◽

Insulin Response ◽

Area Under The Curve ◽

Constant Load ◽

Bicycle Ergometer ◽

The Body ◽

Water Control ◽

Double Blind ◽

Healthy Men

Trehalose increases blood glucose levels slowly and induces a slight insulin response. The present study aimed to study the effect of trehalose on prolonged exercise performance. The participants were 12 healthy men (age: 21.3 ± 0.9 y). After an overnight fast (12 h), they first exercised with a constant load (intensity: 40% V˙O2peak) for 60 min using a bicycle ergometer. They continued to exercise with a constant load (40% V˙O2peak) for 30 min between four sets of the 30-s Wingate test. After the 1st set, each participant ingested 500 mL water (control), 8% glucose, or 8% trehalose in three trials. These three trials were at least one week apart and were conducted in a double-blind and randomized crossover manner. Blood was collected for seven biochemical parameters at 12 time points during the experiment. The area under the curve of adrenaline after ingestion of trehalose was significantly lower than that for water and tended to be lower than that for glucose in the later stage of the exercise. Lower secretion of adrenaline after a single dose of 8% trehalose during prolonged exercise reflected the preservation of carbohydrates in the body in the later stage of the exercise. In conclusion, a single ingestion of trehalose helped to maintain prolonged exercise performance.

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Cardiorespiratory Functioning in Youth with Persistent Post-Concussion Symptoms: A Pilot Study

Journal of Clinical Medicine ◽

10.3390/jcm10040561 ◽

2021 ◽

Vol 10 (4) ◽

pp. 561

Author(s):

Aliyah Snyder ◽

Christopher Sheridan ◽

Alexandra Tanner ◽

Kevin Bickart ◽

Molly Sullan ◽

...

Keyword(s):

Processing Speed ◽

Mean Value ◽

Exhaled Breath ◽

Post Injury ◽

The Past ◽

Neurobehavioral Outcomes ◽

End Tidal ◽

Relationship Of ◽

The Relationship ◽

End Tidal Co2

Dysregulation of the autonomic nervous system (ANS) may play an important role in the development and maintenance of persistent post-concussive symptoms (PPCS). Post-injury breathing dysfunction, which is influenced by the ANS, has not been well-studied in youth. This study evaluated cardiorespiratory functioning at baseline in youth patients with PPCS and examined the relationship of cardiorespiratory variables with neurobehavioral outcomes. Participants were between the ages of 13–25 in two groups: (1) Patients with PPCS (concussion within the past 2–16 months; n = 13) and (2) non-injured controls (n = 12). Capnometry was used to obtain end-tidal CO2 (EtCO2), oxygen saturation (SaO2), respiration rate (RR), and pulse rate (PR) at seated rest. PPCS participants exhibited a reduced mean value of EtCO2 in exhaled breath (M = 36.3 mmHg, SD = 2.86 mmHg) and an altered inter-correlation between EtCO2 and RR compared to controls. Neurobehavioral outcomes including depression, severity of self-reported concussion symptoms, cognitive catastrophizing, and psychomotor processing speed were correlated with cardiorespiratory variables when the groups were combined. Overall, results from this study suggest that breathing dynamics may be altered in youth with PPCS and that cardiorespiratory outcomes could be related to a dimension of neurobehavioral outcomes associated with poorer recovery from concussion.

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