A cafeína aumenta a queima de gordura após treinamento de força

Boa tarde! Segue mais um estudo sobre o efeito da cafeína no exercício. 

 

Boa leitura!

Após um treino extenuante as células musculares precisam de energia para se recuperarem. Elas precisam repor as suas reservas de creatina fosfato e do glicogênio que fora depletado. Sem contar recuperação das fibras musculares, antes danificadas durante a proteólise muscular, processo de síntese proteíca, que demanda muita energia.

 

Há vários anos vem sendo estudado o efeito da cafeína sobre o treinamento físico, e tem se constatado que a cafeína aumenta a disponibilidade de ácidos graxos livres além de aumentar o consumo de oxigênio após um treinamento de força, o EPOC. 

 
Em 1989 e em 1992, Chad  and Quigley mostraram que a cafeína [5 mg/ kg de massa corporal] levantou o EPOC de mulheres não treinadas após uma sessão de treino cardiovascular. [Segue resumo abaixo - Eur J Appl Physiol Occup Physiol. 1989; 59 (1-2):. 48-54] [Eur J Appl Physiol Occup Physiol. 1992; 65 (5): 459-63].

 

Mas isso também aconteceu após uma sessão de treinamento de força. E em homens treinados. De acordo com os resultados mostrados por Astorino e cols., 2011, o suplemento contendo uma dose de 6mg/kg de cafeína aumentou o consumo de oxigênio durante o treinamento, como você pode ver na tabela abaixo. O estimulante também elevou o gasto energético pós-treinamento em 15%. Resumidmente, isso significa que houve uma maior oferta de gordura e menor de glicogênio.

 

 

 

Fonte: J Sports Med Phys Fitness. 2011 Mar;51(1):11-7.

 

 

J Sports Med Phys Fitness. 2011 Mar;51(1):11-7.

Effect of acute caffeine ingestion on EPOC after intense resistance training.

Astorino TA, Martin BJ, Wong K, Schachtsiek L.

Source

Department of Kinesiology, California State University, San Marcos, CA, USA. astorino@csusm.edu

Abstract

AIM:

This study investigated the effect of acute caffeine (CAF) intake on postexercise oxygen consumption (EPOC) after intense resistance training.

METHODS:

Fourteen strength-trained men (mean ± SD age and mass =23.1 ± 4.2 yr and 83.4 ± 13.2 kg, respectively) who were caffeine users initially completed one-repetition maximum testing (1-RM) of four exercises: bench press, leg press, lat row, and shoulder press. On each of two days separated by one week, they completed four sets of each exercise to fatigue at 70-80% 1-RM, which was preceded by ingestion of CAF (6 mg/kg) or placebo. Pre-exercise, indirect calorimetry was used to assess energy expenditure for 35 min; this was repeated for 75 min postexercise while subjects remained seated in a quiet lab. Two-way analysis of variance with repeated measures was used to examine differences in gas exchange variables across time and treatment.

RESULTS:

Results revealed that EPOC was significantly higher (P<0.05) with CAF (26.7 ± 4.1 L) compared to placebo (22.8 ± 3.8 L). With CAF ingestion, oxygen uptake was significantly higher (P<0.05) from 10 min pre-exercise to 70 min postexercise. Respiratory exchange ratio was significantly different (P<0.05) with CAF versus placebo. Caffeine intake increased total energy expenditure by 15% (P<0.05), but the additional calories burned was minimal (+27 kcal).

CONCLUSION:

Caffeine ingestion in individuals regularly completing rigorous resistance training significantly increases EPOC and energy expenditure pre-and post-exercise, yet the magnitude of this effect is relatively small.

PMID: 21297558 [PubMed - indexed for MEDLINE] 

 

 

 

Eur J Appl Physiol Occup Physiol. 1989;59(1-2):48-54.

The effects of substrate utilization, manipulated by caffeine, on post-exercise oxygen consumption in untrained female subjects.

Chad K, Quigley B.

Source

Department of Human Movement Studies, University of Queensland, St. Lucia, Australia.

Abstract

The effect of substrate utilization manipulated by caffeine on post-exercise oxygen consumption was investigated in five untrained females (age = 21 +/- 1.5 years), following 90 min of treadmill walking at 55% maximal oxygen consumption. Each subject participated in the two trials (control and experimental) within 2 weeks of each other. Immediately following the measurement of resting oxygen consumption, subjects consumed one of the two test beverages 60 min prior to exercise: 5 mg of caffeine per kg of body-weight in 200 ml of orange juice (CA) or 200 ml of orange juice (C). Assignment of CA and C was made in a random, double blind fashion. Immediately prior to the exercise phase (0 min) resting oxygen consumption was again measured. Following exercise, subjects returned to the same pre-exercise sitting position where respiratory data was collected over 1 h. No significant differences were found in resting oxygen consumption and respiratory exchange ratio (R) prior to caffeine ingestion (-60 min). One hour after caffeine ingestion (0 min) oxygen consumption and free fatty acid (FFA) levels increased significantly compared to C. During and 1 h following exercise, oxygen consumption and FFA levels were significantly greater, with R values being significantly lower in CA compared to C. These findings provide further evidence that metabolic substrate is somehow implicated in elevating oxygen consumption following exercise cessation.

PMID:2583149 [PubMed - indexed for MEDLINE] 

 

 

Eur J Appl Physiol Occup Physiol. 1992;65(5):459-63.

The effects of two levels of caffeine ingestion on excess postexercise oxygen consumption in untrained women.

Donelly K, McNaughton L.

Source

Centre for Physical Education, University of Tasmania, Launceston, Australia.

Abstract

The effects of two levels of caffeine ingestion (5 mg.kg-1, CAF1, and 10 mg.kg-1, CAF2) on postexercise oxygen consumption was investigated in six untrained women aged 20.5 (SEM 0.5) years. After a test to determine maximal oxygen consumption (VO2max) each subject underwent three test sessions at 55% VO2max either in a control condition (CON) or with the CAF1 or CAF2 dose of caffeine. During exercise, oxygen consumption was found to be significantly higher in the CAF1 and CAF2 trials, compared to CON (P < 0.05). During the hour postexercise, oxygen consumption in CAF1 and CAF2 remained significantly higher than in CON (P < 0.05). At all times throughout the exercise, free fatty acid (FFA) concentrations were significantly higher in the caffeine trials than in CON. The FFA concentrations 1 h postexercise (+60 min) were further elevated above resting values for all three trials. Caffeine ingestion caused the greatest elevation above resting levels being 1.89 (SEM 0.19) mmol.l-1 and 1.96 (SEM 0.22) mmol.l-1 for the CAF1 and CAF2 trials, respectively. This was significantly higher (P < 0.0001) than the CON level which was 0.97 (SEM 0.19) mmol.l-1. Respiratory exchange ratio (R) values became significantly lower (P < 0.05) in CAF1 and CAF2 compared to CON at the onset of exercise and continued to decrease during the activity. Throughout the recovery period, R values were significantly lower for both caffeine trials compared to CON. The results of this study would suggest that caffeine is useful in significantly increasing metabolic rate above normal levels in untrained women during, as well as after, exercising at 55% VO2max.

PMID:1425653 [PubMed - indexed for MEDLINE]