A comparison of the effects of different forms of caffeine supplementation on 5000-metre running performance

BACKGROUND Caffeine is a well established ergogenic aid to enhance sporting performance, and there is a variety of commercially available caffeine supplements. However, there is limited research investigating caffeine effects on running performance and comparing different forms of caffeine supplementation. AIM The purpose of this research was to compare how a moderate dose of caffeine (3- 4.5mg.kg⁻¹ of body mass), administered acutely and in three different supplementation forms (caffeine gum, tablets, and strips), affected 5000-metre track running performance. METHOD Using a randomised, placebo-controlled, crossover design, 10 males (mean ± SD, age 40 ± 9 years, body mass 73.4 ± 10.1kg, height 180.6 ± 10.2cm), and 4 females (age 40.7 ± 8.8 years, height 166.7 ± 6.8cm, body mass 58.5 ± 2kg), completed five x 5000-metre time trials. Trials were conducted at a self-paced maximal effort and took place on an outdoor 400-metre athletics track. Trials were spread over a 9-week period, separated by no less than 3 days and a maximum of 28 days. After conducting a familiarisation, participants ingested a single dose of caffeine (200mg for body mass <65kg or 300mg for body mass >65kg), 10-15 minutes before each trial, in the form of either caffeine chewing gum (CG), caffeine strips (CS), caffeine tablets (CT), or placebo (P). Performance and physiological measurements collected were total time, 800-metre lap pace, heart rate (HR) and rate of perceived exertion (RPE). On completion of each time trial, participants also provided a urine sample for analysis of caffeine and paraxanthine metabolites. RESULTS In comparison with P, caffeine supplementation improved running performance for CT = 2.0% ± 1.1%, CG= 0.9 ± 1.4% and CS= 1.2 ± 1.0 % (95% CL), with only CT significant (p=0.02). Overall pace trended faster in all caffeine trials compared with P and was significant in CT at 2600m-3400m (p=0.013) and 3400m-4200m (p=0.015). Acute caffeine supplementation did not affect HR or RPE. There was no relationship between the urinary concentration content of caffeine, paraxanthine, and associated metabolic ratio and running performance. CONCLUSION This study concludes that 3-4.5mg kg⁻¹ body mass of caffeine, consumed 10-15 minutes before exercise, can produce small yet significant improvements in 5000-metre running performance when taken in tablet form. However, why this only occurred in the tablet supplement is unclear and requires additional research.

Name thesis:degree_name

Master of Health Science

Level thesis:degree_level

Masters

Grantor

Eastern Institute of Technology (EIT)

Year dc:date.issued

2018

Author dc:creator

• Whalley, Peter John Harry

• caffeine
• ergogenic acid
• supplements
• caffeine gum
• caffeine strips
• caffeine tablets
• running performance
• pacing
• rate of perceived exertion (RPE)
• caffeine urinary metabolites
• time trials

Statement dc:rights

• All rights reserved

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10652/6045

OAI identifier oai:identifier

oai:null:10652/6045