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Caffeine Ingestion Increases Estimated Glycolytic Metabolism during Taekwondo Combat Simulation but Does Not Improve Performance or Parasympathetic Reactivation.

Lopes-Silva JP, Silva Santos JF, Branco BH, Abad CC, Oliveira LF, Loturco I, Franchini E - PLoS ONE (2015)

Bottom Line: The aim of this study was to evaluate the effect of caffeine ingestion on performance and estimated energy system contribution during simulated taekwondo combat and on post-exercise parasympathetic reactivation.However, caffeine did not improve performance as measured by attack number (CAF: 26. 7 ± 1.9; PLA: 27.3 ± 2.1, P = 0.48) or attack time (CAF: 33.8 ± 1.9 s; PLA: 36.6 ± 4.5 s, P = 0.58).Caffeine ingestion increased the estimated glycolytic contribution during taekwondo combat simulation, but this did not result in any changes in performance, perceived exertion or parasympathetic reactivation.

View Article: PubMed Central - PubMed

Affiliation: Martial Arts and Combat Sports Research Group, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil.

ABSTRACT

Objectives: The aim of this study was to evaluate the effect of caffeine ingestion on performance and estimated energy system contribution during simulated taekwondo combat and on post-exercise parasympathetic reactivation.

Methods: Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either caffeine (5 mg∙kg-1) or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration and rating of perceived exertion were measured before and after each round, while heart rate (HR) and the estimated contribution of the oxidative (WAER), ATP-PCr (WPCR), and glycolytic (W[La-]) systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated through 1) taking absolute difference between the final HR observed at the end of third round and the HR recorded 60-s after (HRR60s), 2) taking the time constant of HR decay obtained by fitting the 6-min post-exercise HRR into a first-order exponential decay curve (HRRτ), or by 3) analyzing the first 30-s via logarithmic regression analysis (T30).

Results: Caffeine ingestion increased estimated glycolytic energy contribution in relation to placebo (12.5 ± 1.7 kJ and 8.9 ± 1.2 kJ, P = 0.04). However, caffeine did not improve performance as measured by attack number (CAF: 26. 7 ± 1.9; PLA: 27.3 ± 2.1, P = 0.48) or attack time (CAF: 33.8 ± 1.9 s; PLA: 36.6 ± 4.5 s, P = 0.58). Similarly, RPE (CAF: 11.7 ± 0.4 a.u.; PLA: 11.5 ± 0.3 a.u., P = 0.62), HR (CAF: 170 ± 3.5 bpm; PLA: 174.2 bpm, P = 0.12), oxidative (CAF: 109.3 ± 4.5 kJ; PLA: 107.9 kJ, P = 0.61) and ATP-PCr energy contributions (CAF: 45.3 ± 3.4 kJ; PLA: 46.8 ± 3.6 kJ, P = 0.72) during the combat simulation were unaffected. Furthermore, T30 (CAF: 869.1 ± 323.2 s; PLA: 735.5 ± 232.2 s, P = 0.58), HRR60s (CAF: 34 ± 8 bpm; PLA: 38 ± 9 bpm, P = 0.44), HRRτ (CAF: 182.9 ± 40.5 s, PLA: 160.3 ± 62.2 s, P = 0.23) and HRRamp (CAF: 70.2 ± 17.4 bpm; PLA: 79.2 ± 17.4 bpm, P = 0.16) were not affected by caffeine ingestion.

Conclusions: Caffeine ingestion increased the estimated glycolytic contribution during taekwondo combat simulation, but this did not result in any changes in performance, perceived exertion or parasympathetic reactivation.

No MeSH data available.


Related in: MedlinePlus

Rating of perceived exertion (RPE) before and after the warm-up and after each round in CAF and PLA.asignificantly higher than preceding values in CAF and PLA. CAF = Caffeine; PLA = Placebo.
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pone.0142078.g003: Rating of perceived exertion (RPE) before and after the warm-up and after each round in CAF and PLA.asignificantly higher than preceding values in CAF and PLA. CAF = Caffeine; PLA = Placebo.

Mentions: There was no main effect of condition for RPE (F1,9 = 0.27; P = 0.62; η2 = 0.03, [small]), but there was a main effect of round (F4,36 = 105.82; P = 0.01; η2 = 0.92, [large]), with values increasing significantly throughout the combat in both CAF and PLA conditions (P = 0.01). However, there was no condition by round interaction (F3,27 = 1.24; P = 0.31; η2 = 0.12, [small]) (Fig 3).


Caffeine Ingestion Increases Estimated Glycolytic Metabolism during Taekwondo Combat Simulation but Does Not Improve Performance or Parasympathetic Reactivation.

Lopes-Silva JP, Silva Santos JF, Branco BH, Abad CC, Oliveira LF, Loturco I, Franchini E - PLoS ONE (2015)

Rating of perceived exertion (RPE) before and after the warm-up and after each round in CAF and PLA.asignificantly higher than preceding values in CAF and PLA. CAF = Caffeine; PLA = Placebo.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4634755&req=5

pone.0142078.g003: Rating of perceived exertion (RPE) before and after the warm-up and after each round in CAF and PLA.asignificantly higher than preceding values in CAF and PLA. CAF = Caffeine; PLA = Placebo.
Mentions: There was no main effect of condition for RPE (F1,9 = 0.27; P = 0.62; η2 = 0.03, [small]), but there was a main effect of round (F4,36 = 105.82; P = 0.01; η2 = 0.92, [large]), with values increasing significantly throughout the combat in both CAF and PLA conditions (P = 0.01). However, there was no condition by round interaction (F3,27 = 1.24; P = 0.31; η2 = 0.12, [small]) (Fig 3).

Bottom Line: The aim of this study was to evaluate the effect of caffeine ingestion on performance and estimated energy system contribution during simulated taekwondo combat and on post-exercise parasympathetic reactivation.However, caffeine did not improve performance as measured by attack number (CAF: 26. 7 ± 1.9; PLA: 27.3 ± 2.1, P = 0.48) or attack time (CAF: 33.8 ± 1.9 s; PLA: 36.6 ± 4.5 s, P = 0.58).Caffeine ingestion increased the estimated glycolytic contribution during taekwondo combat simulation, but this did not result in any changes in performance, perceived exertion or parasympathetic reactivation.

View Article: PubMed Central - PubMed

Affiliation: Martial Arts and Combat Sports Research Group, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil.

ABSTRACT

Objectives: The aim of this study was to evaluate the effect of caffeine ingestion on performance and estimated energy system contribution during simulated taekwondo combat and on post-exercise parasympathetic reactivation.

Methods: Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either caffeine (5 mg∙kg-1) or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration and rating of perceived exertion were measured before and after each round, while heart rate (HR) and the estimated contribution of the oxidative (WAER), ATP-PCr (WPCR), and glycolytic (W[La-]) systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated through 1) taking absolute difference between the final HR observed at the end of third round and the HR recorded 60-s after (HRR60s), 2) taking the time constant of HR decay obtained by fitting the 6-min post-exercise HRR into a first-order exponential decay curve (HRRτ), or by 3) analyzing the first 30-s via logarithmic regression analysis (T30).

Results: Caffeine ingestion increased estimated glycolytic energy contribution in relation to placebo (12.5 ± 1.7 kJ and 8.9 ± 1.2 kJ, P = 0.04). However, caffeine did not improve performance as measured by attack number (CAF: 26. 7 ± 1.9; PLA: 27.3 ± 2.1, P = 0.48) or attack time (CAF: 33.8 ± 1.9 s; PLA: 36.6 ± 4.5 s, P = 0.58). Similarly, RPE (CAF: 11.7 ± 0.4 a.u.; PLA: 11.5 ± 0.3 a.u., P = 0.62), HR (CAF: 170 ± 3.5 bpm; PLA: 174.2 bpm, P = 0.12), oxidative (CAF: 109.3 ± 4.5 kJ; PLA: 107.9 kJ, P = 0.61) and ATP-PCr energy contributions (CAF: 45.3 ± 3.4 kJ; PLA: 46.8 ± 3.6 kJ, P = 0.72) during the combat simulation were unaffected. Furthermore, T30 (CAF: 869.1 ± 323.2 s; PLA: 735.5 ± 232.2 s, P = 0.58), HRR60s (CAF: 34 ± 8 bpm; PLA: 38 ± 9 bpm, P = 0.44), HRRτ (CAF: 182.9 ± 40.5 s, PLA: 160.3 ± 62.2 s, P = 0.23) and HRRamp (CAF: 70.2 ± 17.4 bpm; PLA: 79.2 ± 17.4 bpm, P = 0.16) were not affected by caffeine ingestion.

Conclusions: Caffeine ingestion increased the estimated glycolytic contribution during taekwondo combat simulation, but this did not result in any changes in performance, perceived exertion or parasympathetic reactivation.

No MeSH data available.


Related in: MedlinePlus