The Impact of a Caffeinated Sports Drink on Performance

Each subject will complete 5 trials (1 familiarization and 4 experimental) consisting of approximately 2 hours cycling in a warm environment (90ºF), followed by strength assessment and cognitive assessment via questionnaire. Each trial will be identical, with the only difference being the type of drink consumed during each trial. The first trial will be for familiarization without any blood sampling. The rest of the trials will be completed in a randomized order and the drink consumed

Cycling Endurance Exercise Performance

The exercise test will consist of a series of three consecutive cycling sets in a warm environment (90ºF), with each series consisting of:

• a 30-min submaximal ride (50% maximal power as determined from the initial)
• a 5-km time trial race-like performance effort. During each 30 min submaximal rides participants will drink a total 500 mL of fluid spread out during the 30 min. During the 5 km performance test the participants will drink 25 mL of fluid at the end of each kilometer.

At regular intervals throughout the exercise task, body weight, blood samples, respiratory gasses, and perceptual data will be collected. See study schematic provided below for specific measurement timepoints.

Upon completion of the cycling task subjects will moved to another room with cool temperature (70ºF), where strength and cognitive function will be assessed to determine the influence of each beverage on indices of exercise performance and fatigue.

Inclusion criteria

• Age 18-55
• Healthy and injury-free (muscle, skeletal) for greater than 2 months
• Active cyclists who train at least 3 times per week
• Body mass index (BMI) range of 18.5-30 kg/m2

Exclusion criteria

• • History of caffeine sensitivity

• Cancer Diagnosis during the last 5 years
• Pregnancy
• History of renal disease, hypertension
• History of a heat stroke
• Use of testosterone therapy
• Adults who are unable to consent (impaired decision-making capacity)