Publication Date


Document Type


First Advisor

Chomentowski, Peter J., III

Degree Name

M.S. Ed. (Master of Education)

Legacy Department

Department of Kinesiology and Physical Education


Kinesiology; Nutrition


Caffeine is one of the most widely used drugs in the world, commonly ingested in coffee, tea, soda, chocolate, and energy drinks, due to its benefits of increasing mental and physical capabilities. Caffeine has also been commonly used as an ergogenic aid when performing repeated-sprint activity. PURPOSE: The purpose of this study is to examine the effects of 200 mg of caffeine during repeated-sprint activity on heart rate, rating of perceived exertion, blood lactate concentration, and sprint time. METHODS: Thirty-two students (Age: 22.19 ± 2.29 years; Height: 170.58 ± 10.18 cm; Weight: 74.78 ± 12.76 kg; BMI: 25.59 ± 2.78) participated in the study. The study followed a randomized crossover trial, in which each participant ingested either 200 mg of caffeine (CAF) or placebo (PLA) 45 minutes prior to each of the two exercise sessions. The sprinting protocol consisted of three sets of six maximal-effort 30-meter sprints. Each single sprint covered a 15-meter distance between the starting line and the secondary marker, such that each subject sprinted down to the secondary marker and back to the starting line. Each of the six sprints in a set were separated by a total of 20 seconds using an active recovery modality. Following each sprint set, heart rate, blood lactate concentration, sprint time, and the rating of perceived exertion were recorded. RESULTS: The caffeine trials were not significantly different than the placebo trials for heart rate and the rating of perceived exertion. However, for the rating of perceived exertion, there was a main effect for time [F(3,93) = 292.810, p < 0.001]. The caffeine trials (Resting: 1.30 ± 0.52 mmol/L; Set 1: 11:33 ± 2.38 mmol/L; Set 2: 13.26 ± 3.02 mmol/L; Set 3: 13.67 ± 2.49 mmol/L) elicited increased blood lactate concentrations compared to the placebo trials (Resting: 1.37 ± 0.53 mmol/L; Set 1: 9.24 ± 2.43 mmol/L; Set 2: 11.46 ± 2.87 mmol/L; Set 3: 11.83 ± 2.55 mmol/L). The caffeine trials (Set 1: 6.78 ± 0.58 secs; Set 2: 6.81 ± 0.55 secs; Set 3: 6.85 ± 0.57 secs) also produced a decreased average sprint time compared to the placebo trials (Set 1: 7.00 ± 0.64 secs; Set 2: 7.02 ± 0.62 secs; Set 3: 7.12 ± 0.63 secs). For the average sprint time, there were significant main effects for condition [F(1,31) = 36.839, p < 0.001] and time [F(2,62) = 5.806, p = 0.006]. CONCLUSION: Caffeine supplementation at a dose of 200 mg elicits an increase in repeated-sprint ability in college-aged non-athletes.


Advisors: Peter J. Chomentowski.||Committee members: Clayton L. Camic; Steven M. Howell; Shuqi Zhang.||Includes illustrations.||Includes bibliographical references.


87 pages




Northern Illinois University

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