Affiliations: [a] Department of Medical Biochemistry, Faculty of
Medicine, University of Balıkesir, Balıkesir, Turkey | [b] Physical Education and Sport, University of
Balıkesir, Balıkesir, Turkey | [c] Department of Pharmacology and Toxicology, Faculty of
Veterinary Medicine, University of Balıkesir, Balıkesir,
Turkey
Note: [] Corresponding author: Zekine Punduk, Physical Education and
Sports, University of Balikesir, PO 10050, Balıkesir, Turkey. Tel.: +90
266 243 6447; Fax: +90 266 239 0285; E-mail: zekine74@yahoo.co.uk
Abstract: BACKGROUND: Commercial energy drink usage is reported to be higher
in athletes and adolescents. However, the impact of pre-exercise consumption of
energy beverages on hematologic and biochemical responses and skeletal muscle
contractile properties has not been fully elucidated. METHOD: Ten male subjects performed 50 maximal eccentric actions on
an isokinetic dynamometer at 90°/sec followed by two identical trials that
were preceded by consuming either a placebo (P) or energy drink (ED) beverage.
The test was repeated after 7–10 days while consuming the alternate
beverage. Complete blood counts and chemistry profile was conducted before and
immediately after exercise. RESULTS: Eccentric contractions resulted in an increased number of
neutrophils (Neut) and decreased lymphocytes (Lymph), decreased eosinophils
(EOS) and did not change basophil (BASO) levels in control. However, the BASO
levels increased immediately after the exercise with P and ED beverage
consumption. In contrast, P and ED beverage consumption had no effect on Neut,
Lymph, MONO or EOS counts after exercise compared to pre-exercise values. Acute
exercise increased creatinine kinase (CK) and decreased phosphorus (Pi) but did
not have any effect on other blood chemistry parameters. The biochemical
profile and eccentric muscle contractile properties were not significantly
affected by any of the beverages. CONCLUSIONS: Consumption of pre-exercise energy drink does not have
a favorable effect on immune blood cells induced in the acute eccentric
exercise model.
Keywords: Eccentric contractions, energy drink, hematologic parameters, biochemical parameters
