Introduction: Studies evaluating caffeinated coffee (CAF) can reveal ergogenic effects; however, studies on the effects of caffeinated coffee on running are scarce and controversial. Aim: To investigate the effects of CAF consumption compared to decaffeinated coffee (DEC) consumption on time trial performances in an 800-m run in overnight-fasting runners. Methods: A randomly counterbalanced, double-blind, crossover, placebo-controlled study was conducted with 12 healthy adult males with experience in amateur endurance running. Participants conducted two trials on two different occasions, one day with either CAF or DEC, with a one-week washout. After arriving at the data collection site, participants consumed the soluble CAF (5.5 mg/kg of caffeine) or DEC and after 60 min the run was started. Before and after the 800-m race, blood pressure and lactate and glucose concentrations were measured. At the end of the run, the ratings of perceived exertion (RPE) scale was applied. Results: The runners were light consumers of habitual caffeine, with an average ingestion of 91.3 mg (range 6–420 mg/day). Time trial performances did not change between trials (DEF: 2.38 + 0.10 vs. CAF: 2.39 + 0.09 min, p = 0.336), nor did the RPE (DEC: 16.5 + 2.68 vs. CAF: 17.0 + 2.66, p = 0.326). No difference between the trials was observed for glucose and lactate concentrations, or for systolic and diastolic blood pressure levels. Conclusion: CAF consumption failed to enhance the time trial performance of an 800-m run in overnight-fasting runners, when compared with DEC ingestion. In addition, no change was found in RPE, blood pressure levels, or blood glucose and lactate concentrations between the two trials.

Purpose: To compare the effects of 8 weeks of two types of interval training, Sprint Interval Training (SIT) and High-Intensity Interval Training (HIIT), on anthropometric measures and cardiorespiratory fitness in healthy young women.Methods: A randomized clinical trial in which 49 young active women [age, 30.4 ± 6.1 years; body mass index, 24.8 ± 3.1 kg.m−2; peak oxygen consumption (VO2peak), 34.9±7.5 mL.kg−1.min−1] were randomly allocated into a SIT or HIIT group. The SIT group performed four bouts of 30 s all-out cycling efforts interspersed with 4 min of recovery (passive or light cycling with no load). The HIIT group performed four bouts of 4-min efforts at 90–95% of peak heart rate (HRpeak) interspersed with 3 min of active recovery at 50–60% of HRpeak. At baseline and after 8 weeks of intervention, waist circumference, skinfolds (triceps, subscapular, suprailiac, abdominal, and thigh), body mass and BMI were measured by standard procedures and cardiorespiratory fitness was assessed by cardiorespiratory graded exertion test on an electromagnetically braked cycle ergometer.Results: The HIIT and SIT groups improved, respectively, 14.5 ± 22.9% (P < 0.001) and 16.9 ± 23.4% (P < 0.001) in VO2peak after intervention, with no significant difference between groups. Sum of skinfolds reduced 15.8 ± 7.9 and 22.2 ± 6.4 from baseline (P < 0.001) for HIIT and SIT groups, respectively, with greater reduction for SIT compared to HIIT (P < 0.05). There were statistically significant decreases in waist circumference (P < 0.001) for the HIIT (−3.1 ± 1.1%) and SIT (−3.3 ± 1.8%) groups, with no significant difference between groups. Only SIT showed significant reductions in body weight and BMI (p < 0.05).Conclusions: Eight weeks of HIIT and SIT resulted in improvements in anthropometric measures and cardiorespiratory fitness, even in the absence of changes in dietary intake. In addition, the SIT protocol induced greater reductions than the HIIT protocol in the sum of skinfolds. Both protocols appear to be time-efficient interventions, since the HIIT and SIT protocols took 33 and 23 min (16 and 2 min of effective training) per session, respectively.

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Polyphenol supplementation may be useful during exercise. However, there is no evidence indicating yerba mate (YM) increases muscle strength. Thus, this study sought to evaluate the effect of acute YM supplementation on muscle strength following the strength test. In a crossover and pilot clinical trial, ten men were divided into two groups, receiving either supplementation with YM or a placebo. One hour after consumption of beverages, the participants were submitted to tests of one-repetition maximum (1 RM) on the bench press and leg press. The average age of the participants was 25.5 ± 4.1 years, and the average body mass index was 24.4 ± 2.9 kg/m². YM was not able to increase muscle strength when compared to the placebo in either the 1RM leg press exercise (YM: 225 ± 56.2 kg, vs. placebo: 223 ± 64.3 kg, p = 0.743, Cohen’s d = 0.03) or in the 1 RM bench press exercise (YM: 59.5 ± 20.7 kg vs. placebo: 59.5 ± 21.5 kg, p = 1.000, Cohen’s d = 0.) In conclusion, acute intake of YM did not change muscle strength in physically active men.