Journal of Sports Science and Medicine
Journal of Sports Science and Medicine
ISSN: 1303 - 2968   
Ios-APP Journal of Sports Science and Medicine
Androit-APP Journal of Sports Science and Medicine
©Journal of Sports Science and Medicine (2015) 14, 648 - 656

Research article
Cardiorespiratory and Metabolic Responses to Loaded Half Squat Exercise Executed at an Intensity Corresponding to the Lactate Threshold
José Luis Maté-Muñoz1, , Raúl Domínguez1, Manuel Barba1, Antonio J. Monroy2, Bárbara Rodríguez3, Pedro Ruiz-Solano1, Manuel V. Garnacho-Castaño4
Author Information
1 Laboratory of Biomechanics and Exercise Physiology, Department of Sport Sciences, Alfonso X el Sabio University, Madrid, Spain
2 Universidad Internacional de la Rioja, La Rioja, Spain
3 Francisco de Vitoria University, Madrid, Spain
4 TecnoCampus, College of Health Sciences, University of Pompeu Fabra, Mataró-Maresme, Barcelona, Spain

José Luis Maté-Muñoz
✉ Laboratory of Biomechanics and Exercise Physiology. Department of Sport Sciences. Avda. Universidad, 1, building C, 3 floor, office C-A15, Villanueva de la Cañada 28691- Madrid, Spain
Publish Date
Received: 11-03-2015
Accepted: 07-07-2015
Published (online): 11-08-2015
Share this article

This study was designed to identify the blood lactate threshold (LT2) for the half squat (HS) and to examine cardiorespiratory and metabolic variables during a HS test performed at a work intensity corresponding to the LT2. Twenty-four healthy men completed 3 test sessions. In the first, their one-repetition maximum (1RM) was determined for the HS. In the second session, a resistance HS incremental-load test was performed to determine LT2. Finally, in the third session, subjects performed a constant-load HS exercise at the load corresponding to the LT2 (21 sets of 15 repetitions with 1 min of rest between sets). In this last test, blood samples were collected for lactate determination before the test and 30 s after the end of set (S) 3, S6, S9, S12, S15, S18 and S21. During the test, heart rate (HR) was telemetrically monitored and oxygen consumption (VO2), carbon dioxide production (VCO2), minute ventilation (VE), respiratory exchange ratio (RER), ventilatory equivalent for O2 (VE·VO2-1) and ventilatory equivalent for CO2 (VE·VCO2-1) were monitored using a breath-by-breath respiratory gas analyzer. The mean LT2 for the participants was 24.8 ± 4.8% 1RM. Blood lactate concentrations showed no significant differences between sets 3 and 21 of exercise (p = 1.000). HR failed to vary between S6 and S21 (p > 1.000). The respiratory variables VO2, VCO2, and VE·VCO2-1 stabilized from S3 to the end of the constant-load HS test (p = 0.471, p = 0.136, p = 1.000), while VE and VE·VO2-1 stabilized from S6 to S21. RER did not vary significantly across exercise sets (p = 0.103). The LT2 was readily identified in the incremental HS test. Cardiorespiratory and metabolic variables remained stable during this resistance exercise conducted at an exercise intensity corresponding to the LT2. These responses need to be confirmed for other resistance exercises and adaptations in these responses after a training program also need to be addressed.

Key words: Aerobic fitness/VO, anaerobic threshold, exercise physiology, strength training

           Key Points
  • It can be identified lactate threshold at half-squat.
  • Exercise intensity is predominantly aerobic.
  • The duration of the half-squat can be maintained over time, ~30 min of discontinuous exercise (21 sets, 15 repetitions, 1 min rest).
  • Lactate threshold intensity may be suitable for older adults, sedentary individuals, patients or subjects with a lower functional capacity and even for resistance sports athletes.
Home Issues About Authors
Contact Current Editorial board Authors instructions
Email alerts In Press Mission For Reviewers
Archive Scope
Supplements Statistics
Most Read Articles
  Most Cited Articles
JSSM | Copyright 2001-2020 | All rights reserved. | LEGAL NOTICES | Publisher

It is forbidden the total or partial reproduction of this web site and the published materials, the treatment of its database, any kind of transition and for any means, either electronic, mechanic or other methods, without the previous written permission of the JSSM.

This work is licensed under a Creative Commons License Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.