scholarly journals Short-term co-ingestion of creatine and sodium bicarbonate improves anaerobic performance in trained taekwondo athletes

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Amir Sarshin ◽  
Vahid Fallahi ◽  
Scott C. Forbes ◽  
Alireza Rahimi ◽  
Majid S. Koozehchian ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
Peak Power ◽  
Anaerobic Performance ◽  
Short Term ◽  
Mean Power ◽  
Post Exercise ◽  
Condition Effect ◽  
Ergogenic Effects ◽  
Before And After ◽  
Over Time

Abstract Background Creatine (CR) and sodium bicarbonate (SB) alone improve anaerobic performance. However, the ergogenic effects of CR and SB co-ingestion on taekwondo anaerobic performance remains unknown. Methods Forty trained taekwondo athletes (21 ± 1 y.; 180.5 ± 7.3 cm; 72.7 ± 8.6 kg) were randomized to: (i) CR and SB (CR + SB; 20 g of CR+ 0.5 g·kg− 1·d− 1 of SB), (ii) CR, (iii) SB, (iv) placebo (PLA), or (v) control (CON) for 5 days. Before and after supplementation, participants completed 3 bouts of a Taekwondo Anaerobic Intermittent Kick Test (TAIKT) to determine changes in peak power (PP), mean power (MP), and fatigue index (FI). Blood lactate (BL) was measured before, immediately following, and 3 min post-TAIKT. Results PP and MP increased over time (P < 0.05) following CR + SB, CR, and SB ingestion, with no changes in the PLA or CON groups. There was a greater increase over time in MP following CR + SB (Absolute Δ: 1.15 ± 0.28 W∙kg67) compared to CR (Absolute Δ: 0.43 ± 0.33 W∙kg67; P < 0.001) and SB (Absolute Δ: 0.73 ± 0.24 W∙kg67; P = 0.03). There were no significant time and condition effect for FI (P > 0.05). BL increased following exercise across all groups; however, CR + SB and SB post-exercise BL was lower compared to CR, PLA, and CON (P < 0.05). Conclusion Short-term CR and SB alone enhance TAIKT performance in trained taekwondo athletes. Co-ingestion of CR and SB augments MP compared to CR and SB alone, with similar PP improvements.

Preexercise Carbohydrate Consumption and Repeated Anaerobic Performance in Pre- and Early-Pubertal Boys

2007 ◽  
Vol 17 (2) ◽  
pp. 140-151 ◽  
Author(s):  
Andrea D. Marjerrison ◽  
Jonah D. Lee ◽  
Anthony D. Mahon
Keyword(s):  
Peak Power ◽  
Anaerobic Performance ◽  
Mean Power ◽  
Wingate Anaerobic Test ◽  
Post Exercise ◽  
Carbohydrate Consumption ◽  
Pubertal Boys ◽  
Anaerobic Test ◽  
Placebo Drink ◽  
Over Time

This study examined the effect of pre exercise carbohydrate (CHO) feeding on performance on a Wingate anaerobic test (WAnT) in 11 boys (10.2 ± 1.3 y old). Four WAnTs with 2 min recovery were performed 30 min after consuming a CHO (1 g CHO/kg) or placebo drink. Peak power (PP) and mean power (MP) were similar between trials. PP ranged from 241.1 ± 82.2 to 223.1 ± 57.9 W with carbohydrate and from 238.2 ± 76.1 to 223.4 ± 52.3 W with placebo. MP ranged from 176.3 ± 58.4 to 151.1 ± 37.5 W with carbohydrate versus 178.0 ± 45.8 to 159.1 ± 32.7 W with placebo. Pre exercise glucose was significantly higher in CHO versus placebo (7.0 ± 1.0 vs. 5.5 ± 0.5 mmol/L), but post exercise values were not different. Blood lactate was similar between trials but increased over time. This study found that the ingestion of a CHO solution before exercise did not influence power output during repeated performances of the WAnT.

A Nonmotorized Treadmill Test to Assess Children’s Short-Term Power Output

2000 ◽  
Vol 12 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Nicola C. Sutton ◽  
David J. Childs ◽  
Oded Bar-Or ◽  
Neil Armstrong
Keyword(s):  
Statistical Analysis ◽  
Power Output ◽  
Peak Power ◽  
Anaerobic Performance ◽  
Treadmill Test ◽  
Short Term ◽  
Mean Power ◽  
Wingate Anaerobic Test ◽  
Post Exercise ◽  
Anaerobic Test

The purpose of this study was to develop a nonmotorized treadmill sprint test (ExNMT) to assess children’s short-term power output, to establish the test’s repeatability, and to compare the results to corresponding Wingate anaerobic test (WAnT) measurements. Nineteen children (aged 10.9±0.3 years) completed 2 ExNMTs and 2 WAnTs. Statistical analysis revealed coefficients of repeatability for the ExNMT that compared very favorably with the WAnT for both peak power (26.6 vs. 44.5 W) and mean power (15.3 vs. 42.1 W). The validity of the ExNMT as a test of anaerobic performance is reflected by significant correlations (p ≤.05) with the WAnT (peak power, r = 0.82; mean power, r = 0.88) and reinforced by the relatively high post-exercise blood lactate concentrations (7.1 ± 1.3 vs. 5.6 ± 1.5 mmol · L−1 for the ExNMT and WAnT, respectively). This study has developed a promising laboratory running test with which to examine young people’s short-term power output.

scholarly journals Does Post-Activation Potentiation Protocols affect Anaerobic Performance in women Taolu Wushu Athletes?

2021 ◽  
Author(s):  
José Afonso ◽  
Hengameh Moradian ◽  
Rasoul Eslami ◽  
Alexandre Martins ◽  
Abdolhossein Parnow
Keyword(s):  
Peak Power ◽  
Performance Enhancement ◽  
Anaerobic Performance ◽  
Fatigue Index ◽  
Short Term ◽  
Mean Power ◽  
Significant Difference ◽  
Strength Based ◽  
Rest Time ◽  
Lactate Levels

Abstract Introduction: Post-activation potentiation has an influence on short duration and high intensity function. This study aimed to answer this question whether post-activation potentiation protocol in different models has effect on anaerobic performance in women Wushu athletes. Methods: Women elite Taolu Wushu athletes participated in current crossover design study. (i) specific Wushu WU (Wushu WU); (ii) Strength-based WU (StreWU); and (iii) Speed-based WU (SpeWU) were performed by Wushu athletes in three inconsecutive days separated by 48 h. Five minutes after each WU protocols, Running-Based Anaerobic Sprint Test (RAST) was performed. Heart rate, immediately, and blood lactate were measured for 4 times: before WU protocols, immediately after WU protocols, before RAST, immediately after RAST.Results: Data analysis revealed significant differences in 4 time points of lactate levels (p=0.001; d=1.71), although no significant difference among protocols was observed. Values of variables obtained from RAST showed that StreWU had a significant impact on minimum power (p<0.05; d=-0.795) comparing to WushuWU and on fatigue index comparing to SpeWU (p<0.05; d=-0.799). No significant differences were found among the WU protocols for peak power and mean power.Conclusion: All WU protocols had mostly the same effect, and PAP was not very effective. Possibly, the WU protocols generated too much fatigue, due to the short-term rest time. However, longer intervals would likely enter the realm of post-activation performance enhancement, which is distinct from PAP.

scholarly journals Disentangling niche theory and beta diversity change

2021 ◽  
Author(s):  
William Godsoe ◽  
Peter J Bellingham ◽  
Elena Moltchanova
Keyword(s):  
Beta Diversity ◽  
Price Equation ◽  
Short Term ◽  
Before And After ◽  
Environmental Requirements ◽  
Habitat Specialists ◽  
Montane Tropical Forest ◽  
Ecological Drift ◽  
Over Time

Beta diversity describes the differences in species composition among communities. Changes in beta diversity over time are thought to be due to selection based on species' niche characteristics. For example, theory predicts that selection that favours habitat specialists will increase beta diversity. In practice, ecologists struggle to predict how beta diversity changes. To remedy this problem, we propose a novel solution that formally measures selection's effects on beta diversity. Using the Price equation, we show how change in beta diversity over time can be partitioned into fundamental mechanisms including selection among species, variable selection among communities, drift, and immigration. A key finding of our approach is that a species' short-term impact on beta diversity cannot be predicted using information on its long-term environmental requirements (i.e. its niche). We illustrate how our approach can be used to partition causes of diversity change in a montane tropical forest before and after an intense hurricane. Previous work in this system highlighted the resistance of habitat specialists and the recruitment of light-demanding species but was unable to quantify the importance of these effects on beta diversity. Using our approach, we show that changes in beta diversity were consistent with ecological drift. We use these results to highlight the opportunities presented by a synthesis of beta diversity and formal models of selection.

Accrual management and the decision to sell or hold shares acquired from the exercise of employee stock options

2020 ◽  
pp. 0000-0000
Author(s):  
Thomas Smith ◽  
G. Ryan Huston ◽  
Richard M. Morton
Keyword(s):  
Stock Option ◽  
Employee Stock Options ◽  
Short Term ◽  
Post Exercise ◽  
Employee Stock Option ◽  
Holding Period ◽  
Before And After ◽  
Accrual Management ◽  
The Impact

This study extends the employee stock option literature by examining the impact of accrual management, before and after stock option exercise, on the timing of sales of shares acquired at exercise. We find evidence that accrual management prior to exercise is positively associated with the decision to quickly sell shares after exercise, facilitating a short-term exercise-and-sell strategy. Alternatively, we find that, among executives initially choosing to hold at exercise, tax incentives appear to drive both post-exercise accrual management and the timing of sale transactions. Specifically, our results suggest that executives use income-increasing accruals during the holding period to bolster their stock option gains sand then sell immediately after satisfying the minimum (twelve month) holding period for long-term capital gain treatment. These results provide context for prior research that found evidence of earnings management leading up to option exercise on the expectation of an immediate sale.

Topical Sodium Bicarbonate: No Improvement in Blood Buffering Capacity or Exercise Performance

2020 ◽  
Vol 15 (7) ◽  
pp. 1005-1011
Author(s):  
Alannah K.A. McKay ◽  
Peter Peeling ◽  
Martyn J. Binnie ◽  
Paul S.R. Goods ◽  
Marc Sim ◽  
...  
Keyword(s):  
Body Weight ◽  
Sodium Bicarbonate ◽  
Peak Power ◽  
Cycling Performance ◽  
Blood Parameters ◽  
Buffering Capacity ◽  
Capillary Blood ◽  
Peak Power Output ◽  
Mean Power ◽  
Experimental Trials

Purpose: To assess the efficacy of a topical sodium bicarbonate (0.3 g/kg body weight NaHCO3) application (PR lotion; Amp Human) on blood buffering capacity and performance in recreationally active participants (study A) and moderately trained athletes (study B). Methods: In Study A, 10 participants completed 2 experimental trials: oral NaHCO3 (0.3 g/kg body weight + placebo lotion) or PR lotion (0.9036 g/kg body weight + oral placebo) applied 90 minutes prior to a cycling task to exhaustion (30-s sprints at 120% peak power output with 30-s rest). Capillary blood was collected and analyzed for pH, bicarbonate, and lactate every 10 minutes throughout the 90-minute loading period and postexercise at 5, 10, and 15 minutes. In Study B, 10 cyclists/triathletes completed 2 experimental trials, applying either PR or placebo lotion 30 minutes prior to a cycling performance task (3 × 30-s maximal sprints with 90-s recovery). Capillary blood samples were collected at baseline, preexercise, and postexercise and analyzed as per study A. Results: In Study A, pH and bicarbonate were significantly elevated from baseline after 10 minutes in the oral NaHCO3 condition and throughout recovery compared with no elevation in the PR lotion condition (P < .001). No differences in cycling time occurred between PR lotion (349 [119] s) and oral NaHCO3 (363 [80] s; P = .697). In Study B, no differences in blood parameters, mean power (P = .108), or peak power (P = .448) were observed between conditions. Conclusions: PR lotion was ineffective in altering blood buffering capacity or enhancing performance in either trained or untrained individuals.

scholarly journals Can we always trust rhinomanometry?

2011 ◽  
Vol 49 (1) ◽  
pp. 46-52
Author(s):  
Helle L. Thulesius ◽  
Anders Cervin ◽  
Max Jessen
Keyword(s):  
Nasal Cavity ◽  
Future Research ◽  
Nasal Airway ◽  
Nasal Surgery ◽  
Short Term ◽  
Nasal Stuffiness ◽  
Before And After ◽  
Over Time ◽  
Active Anterior Rhinomanometry

Objectives: Rhinomanometry before and after decongestion distinguishes a nasal airway organic stenosis from congestion of nasal mucosa in patients with nasal stuffiness. Together with rhinoscopy and patient history, it is used to decide if nasal surgery would benefit the patient. Rhinomanometry measurements should thus be reliable and reproducible. Materials and methods: We performed repetitive active anterior rhinomanometry in 9 persons during 5 months to test reproducibility of nasal airway resistance (NAR) over time. We also did test-retest measurements in several participants. Xylometazoline hydrochloride was applied in each nasal cavity to minimize effects of mucosal variation and the nasal cavity was examined with rhinoscopy. The participants evaluated subjective nasal stuffiness on a visual analogue scale (VAS). Results: The long term mean coefficient of variation (CV) of NAR over time was 27% for the whole group while the short term CV was 7 - 17% for test-retest within an hour. Mean NAR reduction after decongestion was 33%, but 13% of NAR values were not reduced after decongestion. Participants had difficulties estimating stuffiness on a VAS in 15% of the assessments, but there was no correlation between the VAS estimates and NAR. Conclusion: We found a high NAR variation over a period of five months. This implies low long-term rhinomanometry reproducibility and we suggest future research on standardised decongestion to increase the reproducibility.

scholarly journals Acute Effects of an “Energy Drink” on Short-Term Maximal Performance, Reaction Times, Psychological and Physiological Parameters: Insights from a Randomized Double-Blind, Placebo-Controlled, Counterbalanced Crossover Trial

Nutrients ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 992 ◽  
Author(s):  
Chtourou ◽  
Trabelsi ◽  
Ammar ◽  
Shephard ◽  
Bragazzi
Keyword(s):  
Blood Pressure ◽  
Blood Glucose ◽  
Mood State ◽  
Reaction Times ◽  
Energy Drink ◽  
Short Term ◽  
Mean Power ◽  
Double Blind ◽  
Post Exercise ◽  
Double Blind Placebo

The current study examined the relationships between the effects of consuming a caffeine-containing “energy drink” upon (i) short-term maximal performance, (ii) reaction times, and (iii) psychological factors (i.e., mood state, ratings of perceived exertion (RPE), and affective load) and on physiological parameters (i.e., blood pressure and blood glucose). A randomized, double-blind, placebo-controlled, counterbalanced crossover design was implemented in this study. Nineteen male physical-education students (age: 21.2 ± 1.2 years; height: 1.76 ± 0.08 m; body-mass: 76.6 ± 12.6 kg) performed two test sessions: after drinking the “Red Bull’ beverage (RB) and after drinking a placebo (PL). One hour after ingestion of each drink, resting blood glucose and blood pressure were measured and the participants completed the Profile of Mood States questionnaire. Then, after a 5-min warm-up, simple visual reaction time and handgrip force were measured, and the 30-s Wingate test was performed. Immediately after these tests, the RPE, blood glucose, and blood pressure were measured, and the affective load was calculated. Differences between treatments were assessed using two-way repeated measures analyses of variance and paired t-tests, as appropriate. Relationships between the test variables were assessed using Bland–Altman correlations. Significant (i) improvements in peak and mean power output, handgrip force, pre- and post-exercise blood glucose, blood pressure, and vigor and (ii) reductions in reaction times, depression, confusion, fatigue, anger, anxiety, RPE, and affective load scores were observed after RB compared to PL. There were significant correlations of (i) physical performances and reaction times with (ii) RPE, affective load, and pre- and post-exercise blood glucose levels. Gains in peak and mean power were significantly correlated with reductions in fatigue, anxiety (peak power only), and anger (mean power only). The reduction of reaction times was significantly correlated with decreases in confusion and anger and with increases in vigor. Handgrip force and reaction times were significantly correlated with pre- and post-exercise blood pressures. We conclude that RB ingestion has a positive effect on physical performance and reaction times. This effect is related to ergogenic responses in both psychological (i.e., RPE, affective load, and mood state) and physiological (i.e., blood glucose and blood pressure) domains.

Does Sodium-Bicarbonate Ingestion Improve Simulated Judo Performance?

2007 ◽  
Vol 17 (2) ◽  
pp. 206-217 ◽  
Author(s):  
Guilherme Giannini Artioli ◽  
Bruno Gualano ◽  
Desiré Ferreira Coelho ◽  
Fabiana Braga Benatti ◽  
Alessandra Whyte Gailey ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
Peak Power ◽  
Perceived Exertion ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Crossover Design ◽  
Ratings Of Perceived Exertion ◽  
Mean Power ◽  
Double Blind ◽  
Improved Performance

The aim of the present study was to investigate whether pre exercise sodium-bicarbonate ingestion improves judo-related performance. The study used 2 different protocols to evaluate performance: 3 bouts of a specific judo test (n = 9) and 4 bouts of the Wingate test for upper limbs (n = 14). In both protocols athletes ingested 0.3 g/kg of sodium bicarbonate or placebo 2 h before the tests. Blood samples were collected to determine lactate level, and levels of perceived exertion were measured throughout the trials. The study used a double-blind, counterbalanced, crossover design. Ingestion of sodium bicarbonate improved performance in Bouts 2 and 3 of Protocol 1 (P < 0.05), mean power in Bouts 3 and 4 of Protocol 2 (P < 0.05), and peak power in Bout 4 of Protocol 2 (P < 0.05). Ingestion of bicarbonate increased lactate concentration in Protocol 1 (P < 0.05) but not in Protocol 2. Ratings of perceived exertion did not differ between treatments. In conclusion, sodium bicarbonate improves judo-related performance and increases blood lactate concentration but has no effect on perceived exertion.

The Effect of an Aerobic Interval Training Program on Intermittent Anaerobic Performance

1995 ◽  
Vol 20 (4) ◽  
pp. 452-464 ◽  
Author(s):  
Milena C. Gaiga ◽  
David Docherty
Keyword(s):  
Training Program ◽  
Peak Power ◽  
Aerobic Power ◽  
Interval Training ◽  
Training Group ◽  
Cycle Ergometer ◽  
Control Group ◽  
Anaerobic Performance ◽  
Short Term ◽  
Aerobic Interval Training

The effects of a 9-week aerobic interval training program on anaerobic intermittent performance were investigated. Intermittent work consisted of four repeat 30-sec maximal efforts on a cycle ergometer (Wingate test) with 3-min recovery intervals. Thirteen men trained 3 days a week on the cycle ergometer, completing 3-min work-to-rest intervals and progressing from 5 to 10 reps. Relative and absolute values of aerobic power increased significantly for the training group (p <.05). No significant change was observed for the control group (n = 11). The training group demonstrated significant increases in the four anaerobic variables of short-term peak power (SPP), short-term anaerobic capacity (SAC), intermediate-term peak power (IPP), and total work (TW), and across the four 30-sec maximal repeats for anaerobic performance (T1-T4) (p <.05). Greater percentages of increase occurred for IPP and TW, especially during Repeats 3 and 4. The control group only demonstrated a significant increase in SPP for Repeat 3. These data suggest that the type of interval training program used in the study increased aerobic power and also enhanced performance in repeated high intensity, short duration work. Key words: short-term peak power, intermediate-term peak power, total work

Sign in / Sign up

Export Citation Format

Share Document