Comparison of blood lactate concentration and perceived exertion during two clinical treadmill protocols

• Main Author: Ross, James H.
• Other Authors: Ball State University. School of Physical Education.
• Format: Others
• Published: 2011
• Subjects: Blood lactate.; Blood > Analysis.; Exercise > Physiological aspects.; Energy metabolism.
• Online Access: http://cardinalscholar.bsu.edu/handle/handle/185563; http://liblink.bsu.edu/uhtbin/catkey/1036180

The purpose of this study was to determine if previously observed differences in ratings of perceived exertion (RPE) at the same intensities during two graded exercise tests (GXT) were the result of changes in blood lactate concentrations (BLC). Thirteen healthy males (25.3 ±53 yrs.) were maximally tested during two protocols (Bruce and Balke 3.0 mph/2.5 % grade changes every 2 minutes). Subjects were randomly assigned to one GXT and completed the second test after 48 hours; both were completed within one week. Ratings of perceived exertion (RPE) were recorded at the end of each 2 minute stage of the Balke and twice per stage during the Bruce protocol. Blood lactate concentrations (BLC) were collected each minute during both protocols.Results: RPE data was first analyzed using two-way ANOVA (protocol x intensity), and a significant interaction was observed with RPEs being higher at each intensity during the Balke protocol. Mean RPE differences were 1.4, 2.8, and 4.5 for 40, 60, 80% of VO2max respectively. The addition of the BLC at each relative exercise intensity as a covariate in the model suggested that BLC accounted for some of the protocol differences in RPE, at 60 and 80% of VOimax.Conclusion: Differences in RPEs between standard GXT protocols reported in previous studies were due, in part, to differences in BLC. === School of Physical Education