Does caffeine ingestion before a short-term sprint interval training promote body fat loss?

We investigated the effect of caffeine ingestion combined with a 2-wk sprint interval training (SIT) on training-induced reductions in body adiposity. Twenty physically-active men ingested either 5 mg/kg of cellulose as a placebo (PLA, n=10) or 5 mg/kg of caffeine (CAF, n=10) 60 min before each SIT session (13×30 s sprint/15 s of rest). Body mass and skinfold thickness were measured pre- and post-training. Energy expenditure was measured at rest, during exercise, and 45 min after exercise in the first SIT session. Body fat was similar between PLA and CAF groups at pre-training (P>0.05). However, there was a significant decrease in body fat after training in the CAF group (−5.9±4.2%, P<0.05) but not in PLA (1.5±8.0%, P>0.05). There was no difference in energy expenditure at rest and during exercise between PLA and CAF groups (P>0.05), but the post-exercise energy expenditure was 18.3±21.4% greater in the CAF than in the PLA group (P<0.05). In conclusion, caffeine ingestion before SIT sessions induced a body fat loss that may be associated with higher post-exercise energy expenditure.

Caffeine in Brazil: intake, socioeconomic and demographic determinants, and major dietary sources

Background: The objectives of the study were to describe caffeine intake by 10 years of age or older Brazilian individuals and to investigate possible associations with demographic and socioeconomic determinants as well as the major dietary sources. Methods: The data used are from the personal food consumption module (n= 34,003) of a country-representative household budget survey. Consumed foods and beverages were identified during the application of food diaries. Caffeine contents in food and beverage sources were obtained primarily in national publications. Multivariate regressions were calculated to assess the correlations between population factors and caffeine intake. Results: The daily intake per person was estimated as 115.7 mg, ranging from 84.7 mg, for 10­13 years of age children and adolescents, to 139.8 mg, for individuals with no education. The percentage of individuals whom diet reveals daily caffeine intake higher than 400 mg is up to 3.0 %, according to age groups. Males and individuals living in the Northeast or South regions or in the states of Minas Gerais, Rio de Janeiro, and Espírito Santo are likely to ingest higher contents of the substance. The major dietary sources are coffee (63.1 %) and coffee with milk (24.9 %), cola soft drinks (3.6 %) and yerba mate (1.9 %).Conclusions: Caffeine intake in Brazil is below the recommended limit reference value for adults, and the percentage of individuals whom diet reveals excessive content of caffeine is low. Thus, excessive caffeine intake may not be a health issue in Brazil and depends on the domicile and gender. The major source in the Brazilian diet is coffee.