The effects of carbohydrate and protein hydrolysate co-ingestion upon exercise metabolism and cycling performance

The ergogenic effects of acute carbohydrate (CHO) supplementation during prolonged exercise are well established. Recently, a number of studies have examined the potential for the inclusion of protein to further augment these efficacious effects. However, observations at present remain equivocal. Furthermore, there is currently a dearth of knowledge regarding the potential physiologic influences of specific protein sources. Therefore, the purpose of the current study was to determine the efficacy of adding whey protein (CHO-PRO) and hydrolysed marine peptides (CHO-PRO-PEP) to a CHO solution when compared to an equally energetic CHO only beverage. Following an initial familiarisation, 12 recreationally active male volunteers performed three randomised, double blind trials. The trials consisted of a 90-minute steady-state cycle preload corresponding to 50% of predetermined maximal power output, followed by a 5 km time-trial. From the onset of exercise and at 15-minute intervals during the initial preload, participants ingested 180 ml of either: CHO (67 g.hr¯¹ of maltodextrin); CHO-PRO (53.1 g.hr¯¹ of maltodextrin, 13.6 g.hr¯¹ of whey protein concentrate) or CHO-PRO-PEP (53.1 g.hr¯¹ of maltodextrin, 11.0 g.hr¯¹ of whey protein concentrate and 2.4 g.hr¯¹ of protein hydrolysate extracted from salmon). Physiological measures including heart rate, blood glucose and blood lactate were also acquired at 15-minute intervals concomitant to expired gas analysis. No significant differences were observed in time-to-complete the 5 km time-trial regardless of the solution ingested (455.49 ± 16.10; 455.57 ± 18.09 and 454.83 ± 20.75 seconds for CHO, CHO-PRO and CHO-PRO-PEP respectively, p = 0.97). Average and peak power output also demonstrated no statistical significance between treatments (p = 0.71 and p = 0.44, respectively). Conversely, significant interaction effects (condition × time) were apparent for both blood lactate (p = 0.02) and the respiratory exchange ratio (p = 0.007). Heart rate also demonstrated a significant main effect for condition (p = 0.047). No other physiological parameters were significantly different between conditions. This data therefore suggests that CHO-PRO and CHO-PRO-PEP supplementation provide no additional performance enhancing effects in comparison to a typical CHO only solution. However, the inclusion of protein from marine sources within a CHO solution may influence substrate utilisation during prolonged steady-state exercise.

Name dc:type.qualificationname

MSc

Level dc:type.qualificationlevel

Masters

Grantor dc:publisher.institution

University of Hull

Year dc:date.issued

2012

Author dc:creator

• Page, Richard

Advisors dc:contributor.advisor

• Siegler, Jason
• Midgley, Adrian Wayne

• Sport science

Language dc:language

en

Identifier

oai:hull-repository.worktribe.com:4213627

OAI identifier oai:identifier

oai:hull-repository.worktribe.com:4213627