Respiratory exchange ratio - Wikipedia
Oxidation of a molecule of Carbohydrate RER = VCO2/VO2 = 6 CO2/6 O2 = . Oxidation of a Linear relationship between VO2max and exercise intensity. Request PDF on ResearchGate | Modeling and Relationship of years; height ± cm; weight ± kg; VO2max ± ml O2 · kg-1·min- 1). After converting the oxygen consumption at the RER points to. RER is the ratio of carbon dioxide (CO 2) produced to oxygen (O 2) If fat is completely oxidised to CO 2 and H 2 O then the relationships is as follows: C 16 H.
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Exercise intensity and the energy source
Conceived and designed the experiments: Was active in the planning of the study: Controlled the quality of the test procedures: Collected, analyzed and interpreting the data: Received Jul 15; Accepted Nov This article has been cited by other articles in PMC. Abstract Objective To describe different end criteria for reaching maximal oxygen uptake VO2max during a continuous graded exercise test on the treadmill, and to explore the manner by which different end criteria have an impact on the magnitude of the VO2max result.
Methods A sample of individuals women aged 20—85 years performed an exercise test on a treadmill until exhaustion. Gas exchange, heart rate, blood lactate concentration and Borg Scale6—20 rating were measured, and the impact of different end criteria on VO2max was studied;VO2 leveling off, maximal heart rate HRmaxdifferent levels of respiratory exchange ratio RERand postexercise blood lactate concentration.
Conclusions A range of typical end criteria are presented in a random sample of subjects aged 20—85 years.
The choice of end criteria will have an impact on the number of the participants as well as the VO2max outcome.
Difference Between RER and RQ
Suggestions for new recommendations are given. Introduction The measurement of maximal oxygen uptake VO2max has been available for more than half a century and provides useful information about an individual's maximal cardiorespiratory fitness and level of physical performance.
During the exercise test, the technicians' skills and the subjects' motivation and effort are important requirements to ensure valid and reliable results when comparing groups in large epidemiological surveys, as well as for the accurate interpretation of a maximal test for both athletes and patients.
The classical plateau described by Taylor and coworkers is recognized as the gold standard to determine a true VO2max . However, this criterion is not straight forward to use in practical settings .
Thus, there is currently no consensus regarding the assessment of maximal effort during a continuous graded exercise test on the treadmill — especially among women and the elderly — and the knowledge about how different end criteria variables are affected by gender and aging is scarce. Furthermore, the original recommendations are often based on older studies that used measurement equipment and test protocols that are different from those used today and the number of participants was low  or consisted of athletes or children and adolescents  — .
Therefore, the purpose of this study was to describe the different end criteria that are used often for reaching VO2max during a maximal progressive graded exercise test on the treadmill in a healthy sample of 20—year-old men and women, and to explore if the choice of end criteria has an impact on the VO2max value.
All individuals signed written informed consent forms before participating. Study Design This study was a cross-sectional multicenter study involving nine test centers from all regions of Norway. The only inclusion criterion was age-related, and 1, of the subjects were randomly invited to participate in a sub study during —, including a cardiopulmonary exercise test CPET on a treadmill .
Finally, a total of men and women met at the laboratory and completed CPET to exhaustion. Exercise Test Height and body weight were measured to the nearest 0. For that reason, physical inactivity could promote increases in body fat.
On the contrary, physically active and trained subjects exhibit lower RER than untrained subjects in response to comparable workloads Jeukendrup et al. Also, endurance training decreases the RER values, increases the oxidative enzyme activity, O2 uptake and delays the time necessary to reach fatigue status during exercise Messonnier et al. In addition, a single bout of aerobic and resistance exercise has been shown to decrease the RER, at least for the next 24 h post-exercise Jamurtas et al.
However, despite the above findings, the exercise effect on the RER changes has not been quantified. These data suggest that controlling factors affecting RER such as diet and previous exercise, the RER values could be properly considered as an auxiliary physical fitness indicator.
The maximal exercise test is the gold standard to assess the aerobic fitness in healthy subjects, including patient with disabilities Campbell et al. This limiting of maximal exercise test is mainly applied in subjects with reduced exercise tolerance neophyte exercisers, sedentary individuals, or those with either pulmonary disease, coronary artery disease, peripheral arterial disease or musculoskeletal pain Vanhees et al. The RER at the end of one maximal exercise has been shown a significant correlation with changes in exercise capacity Stratmann,and during exercise could be also utilized to evaluate metabolic responses in subjects with reduced exercise tolerance and in physical handicap subjects.
To provide additional experimental evidences regarding possible associations between the RER and physical fitness variables, and also to assess the RER under submaximal conditions as a parameter of physical fitness, we evaluated body fat, maximum O2 uptake VO2maxlactate threshold LTas well as the RER under three different submaximal exercises at fixed workload SEFWin trained and untrained physically healthy active men.
Methods Participants Sixteen healthy male subjects volunteered for the study. Relevant anthropometric characteristics of them are presented in Table 1.Effect of VO2max on RER
Eight subjects were athletes trained at a competitive level 6 tri-athletes and 2 cyclists and eight were untrained subjects, not enrolled in any exercise program; however, they were all physically active at their worksite.