Cardiovascular Fitness and Energy Expenditure Response during a Combined Aerobic and Circuit Weight Training Protocol.
OBJECTIVE
The present study describes the oxygen uptake and total energy expenditure (including both aerobic and anaerobic contribution) response during three different circuit weight training (CWT) protocols of equivalent duration composed of free weight exercises, machine exercises, and a combination of free weight exercises intercalating aerobic exercise.


METHODS
Controlled, randomized crossover designs.


METHODS
Subjects completed in a randomized order three circuit weight training protocols of the same duration (3 sets of 8 exercises, 45min 15s) and intensity (70% of 15 repetitions maximum). The circuit protocols were composed of free weight exercises, machine exercises, or a combination of free weight exercises with aerobic exercise. Oxygen consumption and lactate concentration were measured throughout the circuit to estimate aerobic and anaerobic energy expenditure respectively.


RESULTS
Energy expenditure is higher in the combined exercise protocol (29.9±3.6 ml/kg/min), compared with Freeweight (24.2±2.8ml/kg/min) and Machine (20.4±2.9ml/kg/min). The combined exercise protocol produced the highest total energy expenditure but the lowest lactate concentration and perceived exertion. The anaerobic contribution to total energy expenditure was higher in the machine and free weight protocols compared with the combined exercise protocol (6.2%, 4.6% and 2.3% respectively).


CONCLUSIONS
In the proposed protocols, the combined exercise protocol results in the highest oxygen consumption. Total energy expenditure is related to the type of exercise included in the circuit. Anaerobic contributions to total energy expenditure during circuit weight training may be modest, but lack of their estimation may underestimate total energy expenditure.


BACKGROUND
ClinicalTrials.gov NCT01116856.
Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences, Technical University of Madrid, Madrid, Spain.
Pedro J
PJ
Benito
Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland.|Zurich Center for Integrative Human Physiology (ZIHP), Zurich, Switzerland.
María
M
Alvarez-Sánchez
Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences, Technical University of Madrid, Madrid, Spain.|Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland.|Zurich Center for Integrative Human Physiology (ZIHP), Zurich, Switzerland.
Víctor
V
Díaz
Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences, Technical University of Madrid, Madrid, Spain.|Francisco de Vitoria University, Exercise and Sport Sciences, Madrid, Spain.
Esther
E
Morencos
Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences, Technical University of Madrid, Madrid, Spain.
Ana B
AB
Peinado
Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences, Technical University of Madrid, Madrid, Spain.
Rocio
R
Cupeiro
University of Salerno School of Medicine and Surgery, Department of Musculoskeletal Disorders, Salerno, Italy.|Centre for Sport and Exercise Medicine, Queen Mary University of London, Mile End Hospital, 275 Bancroft Road, London E1 4DG, England, United Kingdom.
Nicola
http://orcid.org/0000-0002-5327-3702
N
Maffulli
D000293:Adolescent; D000328:Adult; D065327:Circuit-Based Exercise / Q000379:methods*; D004734:Energy Metabolism; D015444:Exercise; D005081:Exercise Therapy / Q000379:methods; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D010101:Oxygen Consumption; D014891:Weight Lifting; D055815:Young Adult
D019344:Lactic Acid