Caffeine Enhances All Rates of Physical Exertion

The human body can physically accomplish amazing feats, even with its limitations. A recently published study analyzed existing data on energy intake and expenditure during overfeeding and endurance events (think ultra marathons, arctic trekking, and Tour de France), and added their own data from the 140 day Race Across the USA. They found that the athletes’ energy expenditure dramatically decreased as an event carried on longer and longer. While the body was expending energy up to 15 times its most basic level (basal metabolic rate or BMR) for events lasting less than a day and 3-10 times BMR for multi-day events, energy absorption appeared to be limited to 2.5 times BMR.

Though the unaided GI tract seems to have a limit to the amount of energy it can absorb, the human body has an amazing ability to exert great energy for long periods of time! Let's look at some caffeine studies related to physical performance.

Caffeine may enhance physical performance. The acute effects of caffeine intake on time under tension and power generated during the bench press movement. This study found 20 men who were experienced with resistance exercises and had them complete a bench press test twice. Each time the participants completed the test they received a placebo or 5 mg/kg caffeine 60 minutes before the test. They bench pressed at 70% of their one-repetition-maximum while special equipment measured movement, velocity, and power of the motions. The caffeine supplement increased the movement velocity of the bar during the muscle-lengthening phase of the movement and the total time under tension. This suggests that caffeine can shorten the time needed to perform a repetition without decreasing power or velocity of the contraction phase of the movement.

Caffeine placebo may enhance physical performance at low rates of exertion. Effects of placebo on bench throw performance of Paralympic weightlifting athletes: a pilot study. This study was small and looked at caffeine without giving anyone caffeine, but I still find it interesting. Four male paralympic weightlifting athletes completed a bench throw at various levels of their one-repetition-maximum an hour after receiving no supplement or after taking a supplement they were told contained 6 mg/kg caffeine, but it was really a placebo. The athletes who were told they had taken caffeine performed better with greater mean propulsive velocity at the 50% of their one-repetition-maximum, but when tested at 60%, 70%, or 80% of their maximum there was no difference in their performance. The placebo effect may have been operative in this small group at the lowest weight, but at greater weights the placebo effect wasn’t enough. The researchers acknowledged that it would have been beneficial to have also tested a round with actual caffeine (see the next study below).

Caffeine may enhance physical performance more than placebo at low rates of exertion. Improvement of Lower-Body Resistance-Exercise Performance With Blood-Flow Restriction Following Acute Caffeine Intake. This study had 22 men complete knee extension exercise at 30% repetition maximum with blood flow restriction until exhaustion, 60 minutes after taking a placebo or 6 mg/kg caffeine. Combining the lower weight with blood flow restriction is a method some trainers use to increase strength and muscle mass while using smaller weights. The blood flow restriction was accomplished with an adjustable cuff and settings were based on individual measurements. Caffeine ingestion increased the number of repetitions completed while also reducing pain sensation. Another interesting note in this study is that they asked participants to identify if they felt they had taken the placebo or the caffeine. Even the participants who failed to identify they had taken the caffeine supplement completed more repetitions after taking the actual caffeine supplement.

Editor Note

Thrivous Surge Acute Nootropic is an excellent source of Caffeine. It provides 100 mg Caffeine per serving of 1 capsule. That's approximately the amount of Caffeine in a cup of coffee. Each capsule also contains clinical doses of L Theanine and Panax Ginseng, which generally improve the effects of Caffeine by decreasing jitters and improving focus. Thrivous Surge is designed for occasional use, to improve both physical and cognitive performance for peak productivity when you need it most.