Aerobic Capacity Test Research Articles

Resveratrol Supplementation Reduces Aortic Atherosclerosis and Calcification and Attenuates Loss of Aerobic Capacity in a Mouse Model of Uremia

The polyphenolic compound resveratrol (RSV) has been studied for its protective effects on a variety of conditions, including cardiovascular disease (CVD), reduced exercise capacity, and bone disease. Individuals with chronic kidney disease suffer from a variety of these comorbid conditions, but the efficacy of RSV supplementation in this population is unknown. The objective of this study was to determine the efficacy of resveratrol feeding on factors related to CVD, aerobic capacity, and bone health in a mouse model of uremia. At 8 weeks of age, 28 female apolipoprotein E⁻/⁻ mice underwent a two-step surgical procedure to induce uremia and were randomized to one of the two treatment groups for 16 weeks: 0.04% w/w resveratrol supplemented diet (group designated as RSV) (n=12) or control diet (group designated as CON) (n=16). Cardiovascular risk was determined by analysis of aortic atherosclerotic lesion area and aortic calcium, aerobic capacity was measured by maximal oxygen consumption/maximal aerobic capacity (VO(₂max)) testing, and bone microarchitecture was assessed by microcomputed tomography. RSV animals had significantly fewer aortic atherosclerotic lesions at the site of the ascending aorta and lower aortic calcium at the branch of the coronary arteries compared with CON. Furthermore, there was a significant decline in VO(₂max) from baseline to final testing in the CON group, but VO(₂max) was preserved in the RSV group. Last, RSV had no significant effect on bone architecture. These data indicate that RSV supplementation improves vascular health and preserves aerobic capacity in a model of uremia, suggesting RSV supplementation could be examined as a therapeutic strategy for a critically ill population.

Determinants of maximal oxygen uptake (VO2 max) in fire fighter testing

The aim of this study was to evaluate current daily practice of aerobic capacity testing in Belgian fire fighters. The impact of personal and test-related parameters on the outcome has been evaluated.Maximal oxygen uptake (VO2 max) results of 605 male fire fighters gathered between 1999 and 2010 were analysed. The maximal cardio respiratory exercise tests were performed at 22 different centres using different types of tests (tread mill or bicycle), different exercise protocols and measuring equipment.Mean VO2 max was 43.3 (SD = 9.8) ml/kg.min. Besides waist circumference and age, the type of test, the degree of performance of the test and the test centre were statistically significant determinants of maximal oxygen uptake.Test-related parameters have to be taken into account when interpreting and comparing maximal oxygen uptake tests of fire fighters. It highlights the need for standardization of aerobic capacity testing in the medical evaluation of fire fighters.

Measurement Agreement Between Estimates of Aerobic Fitness in Youth: The Impact of Body Mass Index

Purpose The purpose of this study was to examine the impact of body mass index (BMI) on the agreement between aerobic capacity estimates from different Progressive Aerobic Cardiorespiratory Endurance Run (PACER) equations and the Mile Run Test. Method The agreement between 2 different tests of aerobic capacity was examined on a large data set from 2 suburban school districts (n = 1,686 youth in Grades 3–10). Difference estimates between the Mile Run Test and several PACER equations were computed, and residuals were examined using cluster analysis. The implication of the discrepancy between these tests was also examined using FITNESSGRAM® health-related standards for BMI. Comparisons were made against corresponding estimates of peak oxygen consumption from the Mile run because this equation is more established. Results Results supported a 2-cluster solution. The discrepancy between tests was higher in participants with higher BMI scores (Z scores for residuals in this group ranged from − 0.07 to 1.57). BMI was able to explain 30% to 34% of the disagreement between the Mile and different PACER equations of aerobic fitness. Classification analyses revealed that kappa scores were lower among PACER equations that do not include a BMI term (kappa = .12–.34 vs. .59–.81). Overall, the test-equating approach used in the Fitnessgram program to process PACER data had better agreement than alternative PACER equations that included BMI. Conclusion The results support the inclusion of BMI in prediction equations used to estimate aerobic capacity from the PACER.

The effect of puberty on fat oxidation rates during exercise in overweight and normal-weight girls

Excess weight is often associated with insulin resistance (IR) and may disrupt fat oxidation during exercise. This effect is further modified by puberty. While studies have shown that maximal fat oxidation rates (FOR) during exercise decrease with puberty in normal-weight (NW) and overweight (OW) boys, the effect of puberty in NW and OW girls is unclear. Thirty-three NW and OW girls ages 8-18 yr old completed a peak aerobic capacity test on a cycle ergometer. FOR were calculated during progressive submaximal exercise. Body composition and Tanner stage were determined. For each participant, a best-fit polynomial curve was constructed using fat oxidation vs. exercise intensity to estimate max FOR. In a subset of the girls, IR derived from an oral glucose tolerance test (n = 20), and leptin and adiponectin levels (n = 11) were assessed in relation to FOR. NW pre-early pubertal girls had higher max FOR [6.9 ± 1.4 mg·kg fat free mass (FFM)(-1)·min(-1)] than NW mid-late pubertal girls (2.2 ± 0.9 mg·kg FFM(-1)·min(-1)) (P = 0.002), OW pre-early pubertal girls (3.8 ± 2.1 mg·kg FFM(-1)·min(-1)), and OW mid-late pubertal girls (3.3 ± 0.9 mg·kg FFM(-1)·min(-1)) (P < 0.05). Bivariable analyses showed positive associations between FOR with homeostatic model assessment of IR (P = 0.001), leptin (P < 0.001), and leptin-to-adiponectin ratio (P = 0.001), independent of percent body fat. Max FOR decreased in NW girls during mid-late puberty; however, this decrease associated with puberty was blunted in OW girls due to lower FOR in pre-early puberty. The presence of IR due to obesity potentially masks the effect of puberty on FOR during exercise in girls.

Atrial Fibrillation Innovation Program: Transitioning Emergency Atrial Fibrillation Management (Team) - Lessons From A Feasibility Trial

s S99 single-shot acquisition T1 mapping sequence. Subjects also performed peak aerobic capacity (VO2) testing, a vertical jump test, and a wall squat test. RESULTS: Compared to controls, cancer survivors had significantly lower LVEF (57.5 6.2% vs. 64.3 5.5%, P<0.001), LV indexed mass (48.9 13.7 g/m vs. 62.7 10.2 g/m, P<0.001), LV mass/volume ratio (0.67 0.17 vs. 0.89 0.17, P<0.001), and peak VO2 (28.1 4.9 mL/kg/ min vs. 33.8 4.9 mL/kg/min, P<0.01). Between survivors and controls, there was no difference in myocardial ECVF (19.8 1.9% vs. 19.8 2.3%, P1⁄40.95), thigh ECVF (5.6 0.9% vs. 5.9 1.1%, P1⁄40.25), vertical jump distance (35.2 10.1 cm vs. 40.4 11.6 cm, P1⁄40.10), or wall squat duration (91 53 s vs. 111 58 s, P1⁄40.24). Myocardial ECVF and thigh ECVF were unrelated to cumulative anthracycline dose (r1⁄4-0.10, P1⁄40.54, and r1⁄4-0.11, P1⁄40.52, respectively). CONCLUSION: Asymptomatic childhood cancer survivors have significantly lower LVEF, LV mass, and LV mass/volume ratio, compared to controls, suggesting that conventional MRI is sensitive to early changes associated with anthracycline cardiotoxicity. Myocardial and thigh ECVF were similar between survivors and controls, suggesting that fibrosis is not a major component of these gross structural and functional changes. Long-term serial follow-up of a larger group of cancer survivors could provide further insight into the role of MRI in assessment of anthracyline cardiotoxicity in individual subjects. ACHRI Canadian Cardiovascular Society (CCS) Poster ATRIAL FIBRILLATION CLINICAL Thursday, October 17, 2013 030 ATRIAL FIBRILLATION INNOVATION PROGRAM: TRANSITIONING EMERGENCY ATRIAL FIBRILLATION MANAGEMENT (TEAM) LESSONS FROM A FEASIBILITY TRIAL N Meshkat, K Leblanc, S Bhatia, P Dorian, N Ivers, A Valentinis, L Ashley, AC Ha, K Benson, D Morra

Field Tests for Evaluating the Aerobic Work Capacity of Firefighters

Working as a firefighter is physically strenuous, and a high level of physical fitness increases a firefighter’s ability to cope with the physical stress of their profession. Direct measurements of aerobic capacity, however, are often complicated, time consuming, and expensive. The first aim of the present study was to evaluate the correlations between direct (laboratory) and indirect (field) aerobic capacity tests with common and physically demanding firefighting tasks. The second aim was to give recommendations as to which field tests may be the most useful for evaluating firefighters’ aerobic work capacity. A total of 38 subjects (26 men and 12 women) were included. Two aerobic capacity tests, six field tests, and seven firefighting tasks were performed. Lactate threshold and onset of blood lactate accumulation were found to be correlated to the performance of one work task (rs = −0.65 and −0.63, p<0.01, respectively). Absolute (mL·min−1) and relative (mL·kg−1·min−1) maximal aerobic capacity was correlated to all but one of the work tasks (rs = −0.79 to 0.55 and −0.74 to 0.47, p<0.01, respectively). Aerobic capacity is important for firefighters’ work performance, and we have concluded that the time to row 500 m, the time to run 3000 m relative to body weight (s·kg−1), and the percent of maximal heart rate achieved during treadmill walking are the most valid field tests for evaluating a firefighter’s aerobic work capacity.

Effects of Two Different Training Methods in Women With Fibromyalgia Syndrome

The aim of this study was to investigate the effects generated by the methods of training in women with fibromyalgia. Two methods were applied—aerobic training (TA) and circuit training (TCIRC)—and their effects were compared on the quality of life of patients through diagnostic tests for fibromyalgia (questionnaire on the impact of fibromyalgia, visual scale of pain), development of aerobic capacity (test time, VO2max, and HRmax), and strength (15RM test). With the analysis performed in the pre- and post-training periods, it was found that in diagnosis of fibromyalgia the TCIRC had a greater development than the TA when pre- and post-test evolution were compared. In 6 weeks, however, the TA had better results than the TCIRC in aerobic capacity, considering the duration of the training period. In the variable strength development, as expected, the TCIRC showed a higher evolution. Thus, it was concluded that circuit training can be an alternative form of treatment of fibromyalgia.

Construct validity of functional capacity tests in healthy workers.

BackgroundFunctional Capacity (FC) is a multidimensional construct within the activity domain of the International Classification of Functioning, Disability and Health framework (ICF). Functional capacity evaluations (FCEs) are assessments of work-related FC. The extent to which these work-related FC tests are associated to bio-, psycho-, or social factors is unknown. The aims of this study were to test relationships between FC tests and other ICF factors in a sample of healthy workers, and to determine the amount of statistical variance in FC tests that can be explained by these factors.MethodsA cross sectional study. The sample was comprised of 403 healthy workers who completed material handling FC tests (lifting low, overhead lifting, and carrying) and static work FC tests (overhead working and standing forward bend). The explainable variables were; six muscle strength tests; aerobic capacity test; and questionnaires regarding personal factors (age, gender, body height, body weight, and education), psychological factors (mental health, vitality, and general health perceptions), and social factors (perception of work, physical workloads, sport-, leisure time-, and work-index). A priori construct validity hypotheses were formulated and analyzed by means of correlation coefficients and regression analyses.ResultsModerate correlations were detected between material handling FC tests and muscle strength, gender, body weight, and body height. As for static work FC tests; overhead working correlated fair with aerobic capacity and handgrip strength, and low with the sport-index and perception of work. For standing forward bend FC test, all hypotheses were rejected. The regression model revealed that 61% to 62% of material handling FC tests were explained by physical factors. Five to 15% of static work FC tests were explained by physical and social factors.ConclusionsThe current study revealed that, in a sample of healthy workers, material handling FC tests were related to physical factors but not to the psychosocial factors measured in this study. The construct of static work FC tests remained largely unexplained.

Effects of Varied Combinations of Resistance Training Aerobic Training and Yogic Practices on Aerobic Capacity and Cardiovascular Parameters of Obese Adolescent Children

The purpose of this study was to investigate the effect of varied combinations of resistance training, aerobic training and yogic practices on cardiorespiratory fitness of obese adolescent children. To fulfill the purpose of this study forty five (45) male obese subjects having BMI 30.0 – 39.9 were selected for the study. Their age ranged between 10 to 14 years. These subjects were randomly distributed in three groups namely resistance aerobic training group (RATG), resistance and yoga training group (RYTG) and control group (CG) each group consisting of 15 subjects each. All subjects undergo serious health checkup prior to the study to avoid death during training or testing. Each subject reported to the Department of Physical Education, E. R. Higher Secondary School, Trichy and they were tested aerobic capacity before and after training. Aerobic capacity was measured by one mile run and walk test. Prior to the formal study sessions, a pilot study was conducted to validate research procedure and the initial capacity of the participants to design the training programme. The RATG and RYTG group underwent 8 weeks of training. The result showed that adjusted post test of aerobic capacity, resting heart rate and systolic blood pressure found to be significant. However, diastolic blood pressure showed no significant difference among the groups. The covariate is significant, indicating that aerobic capacity, resting heart rate and systolic blood pressure before training had a significant improvement after 8 weeks of training. RATG is better than RYTG in improving cardiorespiratory fitness of obese children.

Exercise improves reaction time without compromising accuracy in a novel easy-to-administer tablet-based cognitive task

Moderate intensity aerobic exercise is known to facilitate cognitive performance but new technologies enable increasing opportunities to investigate this phenomenon under different circumstances. This study aimed to describe the effect of exercise on executive function assessed though a novel tablet-based test. Twenty healthy, active participants volunteered to take part in the randomised fully controlled trial. Participants undertook an initial test of maximal aerobic capacity as well as ventilatory threshold during an incremental cycle test. A touch screen tablet computer was placed in the middle of the handlebars at an angle of approximately 45°, and participants were asked to complete the response-inhibition cognitive task (Speed Match, Lumos Labs Inc.) at set time points. A full familiarisation trial was performed prior to subsequent visits, in which participants completed either the control (no exercise) and exercise (90% ventilatory threshold (VT)) trials in a randomised order. During the 1h trials, the cognitive task was performed prior to, during and post the intervention. Reaction time and accuracy of participant responses were recorded. Performing the cognitive task resulted in elevated heart rates and ventilation rates during control and exercise. Exercise facilitated performance in the executive function task such that reaction time was enhanced with no change in accuracy. A range of reliability measures are also reported. This method of assessing executive function during exercise displays face validity and provides promise for further investigation of cognitive function using a simple, short duration, easily administered and widely available test.

Influence of mouthguards on the physical performance of soccer players

To evaluate the influence of different types of mouthguard (MG) on physical performance of female soccer players. The sample was composed of 25 female soccer players from 'Guarani Futebol Clube', age range 18-22years. For data collection, two tests were performed: agility test (shuttle run) and aerobic capacity and VO2 (Cooper test), in addition to application of a perception questionnaire after wearing mouthguards during the tests. Data analysis showed that mouthguard type III presented better results in the VO2 and aerobic capacity tests (P<0.05). In relation to difficulties experienced when wearing MGs, there were no reports of pain, discomfort, or nausea. However, 100% of athletes affirmed that it was not possible to speak with MG type I, 80% (n=20) with type II, and no athlete found difficulty in speaking when wearing MG type III. Distractions were reported by 35% (n=6) only when athletes wore MG types I and II. Among the three types evaluated, the customized MG (type III) presented better results in the athletes' physical performance evaluation, even taking into account physical tests performed without the use of mouthguards.

Physiological and Physical Characteristics of Elite Dragon Boat Paddlers

The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.

A Pilot Randomized, Placebo Controlled, Double Blind Phase I Trial of the Novel SIRT1 Activator SRT2104 in Elderly Volunteers

BackgroundSRT2104 has been developed as a selective small molecule activator of SIRT1, a NAD+-dependent deacetylase involved in the regulation of energy homeostasis and the modulation of various metabolic pathways, including glucose metabolism, oxidative stress and lipid metabolism. SIRT1 has been suggested as putative therapeutic target in multiple age-related diseases including type 2 diabetes and dyslipidemias. We report the first clinical trial of SRT2104 in elderly volunteers.MethodsOral doses of 0.5 or 2.0 g SRT2104 or matching placebo were administered once daily for 28 days. Pharmacokinetic samples were collected through 24 hours post-dose on days 1 and 28. Multiple pharmacodynamic endpoints were explored with oral glucose tolerance tests (OGTT), serum lipid profiles, magnetic resonance imaging (MRI) for assessment of whole body visceral and subcutaneous fat, maximal aerobic capacity test and muscle 31P magnetic resonance spectroscopy (MRS) for estimation of mitochondrial oxidative capacity.ResultsSRT2104 was generally safe and well tolerated. Pharmacokinetic exposure increased less than dose-proportionally. Mean Tmax was 2–4 hours with elimination half-life of 15–20 hours. Serum cholesterol, LDL levels and triglycerides decreased with treatment. No significant changes in OGTT responses were observed. 31P MRS showed trends for more rapid calculated adenosine diphosphate (ADP) and phosphocreatine (PCr) recoveries after exercise, consistent with increased mitochondrial oxidative phosphorylation.ConclusionsSRT2104 can be safely administered in elderly individuals and has biological effects in humans that are consistent with SIRT1 activation. The results of this study support further development of SRT2104 and may be useful in dose selection for future clinical trials in patients.Trial RegistrationClinicalTrials.gov NCT00964340

Skeletal Muscle Mitochondrial Energetics Are Associated With Maximal Aerobic Capacity and Walking Speed in Older Adults

Lower ambulatory performance with aging may be related to a reduced oxidative capacity within skeletal muscle. This study examined the associations between skeletal muscle mitochondrial capacity and efficiency with walking performance in a group of older adults. Thirty-seven older adults (mean age 78 years; 21 men and 16 women) completed an aerobic capacity (VO2 peak) test and measurement of preferred walking speed over 400 m. Maximal coupled (State 3; St3) mitochondrial respiration was determined by high-resolution respirometry in saponin-permeabilized myofibers obtained from percutanous biopsies of vastus lateralis (n = 22). Maximal phosphorylation capacity (ATPmax) of vastus lateralis was determined in vivo by (31)P magnetic resonance spectroscopy (n = 30). Quadriceps contractile volume was determined by magnetic resonance imaging. Mitochondrial efficiency (max ATP production/max O2 consumption) was characterized using ATPmax per St3 respiration (ATPmax/St3). In vitro St3 respiration was significantly correlated with in vivo ATPmax (r (2) = .47, p = .004). Total oxidative capacity of the quadriceps (St3*quadriceps contractile volume) was a determinant of VO2 peak (r (2) = .33, p = .006). ATPmax (r (2) = .158, p = .03) and VO2 peak (r (2) = .475, p < .0001) were correlated with preferred walking speed. Inclusion of both ATPmax/St3 and VO2 peak in a multiple linear regression model improved the prediction of preferred walking speed (r (2) = .647, p < .0001), suggesting that mitochondrial efficiency is an important determinant for preferred walking speed. Lower mitochondrial capacity and efficiency were both associated with slower walking speed within a group of older participants with a wide range of function. In addition to aerobic capacity, lower mitochondrial capacity and efficiency likely play roles in slowing gait speed with age.

Modeling and Relationship of Respiratory Exchange Ratio to Athletic Performance

Previous research has related the results of tests of maximum aerobic capacity to performance for endurance athletes. These results are often only able to predict the running velocity of races such as the marathon. This investigation sought to determine the absolute V[Combining Dot Above]O2 at various respiratory exchange ratio (RER) values (0.85, 0.90, 0.95, 1.0, 1.05, and 1.10) by using a third-order polynomial regression to model the physiological responses for V[Combining Dot Above]O2 and RER obtained from an assessment of maximum aerobic capacity. The V[Combining Dot Above]O2 determined was subsequently correlated to race performance. The participants in the study were selected from a population of National Collegiate Athletic Association Division 1 crosscountry runners (male n = 7, female n = 7, age 20.5 ± 0.9 years; height 170.3 ± 8.2 cm; weight 59.7 ± 8.7 kg; V[Combining Dot Above]O2max 57.0 ± 7.8 ml O2·kg·min). Third-order regression analysis resulted in strong curve fitting between the variables (r = 0.949 ± 0.03). Partial correlations (controlled for weight) were used to assess the relationship between oxygen consumption at the desired points of RER and race performance. The partial correlations revealed that the absolute oxygen consumptions at all RER points of interest were significantly correlated to race performance (r > 0.740, p < 0.01). There was a significant difference in the strength of the correlations for the points RER 0.95 (t = 2.68957, p = 0.01), 1.0 (t = 2.18516, p = 0.03), and 1.05 (t = 1.85668, p = 0.04) and the correlations found for RER 0.85. After converting the oxygen consumption at the RER points to estimated horizontal running speeds, only the estimate at RER 1.05 was not statistically different from the actual speed achieved in the culminating XC race. It can be suggested based upon these results that coaches of collegiate crosscountry runners who engage in metabolic testing of athletes examine the estimated running pace at RER 1.05 to gain an insight into a runner's potential.

Follow up of aerobic capacity in children affected by severe acute respiratory syndrome

ABSTRACT Background and objective: The aim of this study was to investigate the aerobic capacity of children 3 years after they were diagnosed with severe acute respiratory syndrome (SARS). Methods: Twenty‐seven patients who completed both pulmonary function and maximal aerobic capacity tests at 6 and 15 months after the acute illness were invited to return for reassessment. Results: Twenty‐one patients (median age 18.2 years, interquartile range (IQR) 16.5–19.7) completed all investigations at 36 months. Pulmonary function was normal in all patients. Maximal aerobic capacity, peak oxygen pulse (peak VO2) and ventilatory anaerobic threshold showed significant improvements compared with values measured at 6 months in both boys and girls. In girls, ventilatory efficiency (ventilatory equivalents for oxygen and carbon dioxide) and perfusion of the lungs (end‐tidal partial carbon dioxide pressure) had not increased further compared with the values measured at 15 months. Although peak VO2 improved further at 36 months in patients with or without persistent radiological abnormalities, the values were 68% (IQR 50–84) and 74% (IQR 60–99), respectively, of those for normal control subjects. Conclusions: There were improvements in aerobic capacity at 36 months in children affected by SARS; however, the measured values remained suboptimal.

Fitness Characteristics of a Suburban Special Weapons and Tactics Team

Special Weapons and Tactics (SWAT) operators are specialized law enforcement officers who traditionally perform their duties with higher anticipated workloads because of additional body armor, weapons, and equipment used for enhanced operations and protection. This elevated workload increases the need for SWAT operators to improve or maintain their physical fitness to consistently perform routine operations. Typical tasks require trunk rotation, overhead upper extremity use, upper and lower body strength use, and long waiting periods followed by explosive movements while wearing additional equipment. Eleven male SWAT operators from 1 SWAT team performed flexibility, strength, power, and aerobic capacity tests and a variety of job-related tasks. Data were compared with age- and gender-based normative data. Fitness testing revealed that officers ranked high on tests of muscular strength (leg strength, 90th percentile; bench press, 85th percentile); however, body composition (55th percentile), core body strength, and flexibility ranked lower. Furthermore, aerobic capacity and muscular power had a wide range of scores and were also not ideal to support maximal performance during routine operations. These data can assist exercise specialists choose fitness programs specifically for job-related tasks of SWAT operators when creating fitness programs. Fitness programming for law enforcement should focus on improving aerobic fitness, flexibility, core strength, and muscular power while maintaining muscular strength to meet the needs of these specialized officers.

Aerobic Capacity Testing With Inactive Individuals: The Role of Subjective Experience

Maximal oxygen uptake (VO2max), an assessment of cardiorespiratory fitness, is regularly used as the primary outcome in exercise interventions. Many criteria have been suggested for validating such tests-most commonly, a plateau in oxygen consumption. The current study investigated the proportion of inactive individuals who reached a plateau in oxygen uptake and who achieved a valid test as assessed by secondary criteria (RERmax ≥ 1.1; RPEmax ≥ 18; age predicted HRmax ±10bpm), and the correlates of a successful plateau or achievement of secondary criteria during a VO2max session. Participants (n = 240) were inactive individuals who completed VO2max assessments using an incremental treadmill test. We explored physical, behavioral, and motivational factors as predictors of meeting criteria for meeting a valid test. Approximately 59% of the sample achieved plateau using absolute (increase of VO2 of 150ml O2 or less) and 37% achieved plateau using relative (increase of VO2 of 1.5ml/kg O2 or less) criteria. Being male, having a higher BMI, a greater waist-to-hip ratio, and increased self-efficacy were associated with lower odds of achieving an absolute plateau, whereas none of these factors predicted odds of achieving relative plateau. Findings raise questions about the validity of commonly used criteria with less active populations.

Measurement of Distance Walked and Physiologic Responses to a 6-Minute Walk Test on Level Ground and on a Treadmill

The 6-minute walk test (6MWT) is commonly used to test the functional capacity of individuals. However, in many practice settings, the long corridor needed to administer the test may not be available. Review of current literature revealed limited evidence regarding the use of a treadmill as an alternate method of performing a 6MWT. This study compared the distance walked and the heart rate (HR) response during a 6MWT on level ground (LG) and on a treadmill. A total of 35 healthy adults were in 1 of 3 age groups (45-54, 55-64, and 65-75 years old). Each participant performed level ground (LG) and Treadmill (TM) 6MWT on consecutive test days. Participants completed each test condition twice on the same day. Data from the second trial were used for the analysis. A mixed- model, multivariate analysis of variance was used with 2 factors: age group and test condition. Dependent variables included distance walked and HR response as a proportion of HR reserve. There were no significant differences among the 3 age groups in the distance walked or the HR response during the 6MWT (P = .40, .17, .80) or between the test conditions (TM and LG) (P = .87 and .06). Among healthy adults from middle to old age, a TM 6MWT is an appropriate test of functional and aerobic capacity as determined by measurement of the distance walked and HR response.

The physiology of world‐class sprint skiers

The present study investigated the physiological characteristics of eight world-class (WC) and eight national-class (NC) Norwegian sprint cross country skiers. To measure the physiological response and treadmill performance, the skiers performed a submaximal test, a peak aerobic capacity (VO2peak) test, and a peak treadmill speed (V(peak)) test in the skating G3 technique. Moreover, the skiers were tested for G3 acceleration outdoors on asphalt and maximal strength in the lab. The standard of sprint skating performance level on snow was determined by International Ski Federation points, and the training distribution was quantified. WC skiers showed 8% higher VO2peak and twice as long a VO(2) plateau time at the VO2peak test, and a higher gross efficiency at the submaximal test (all P<0.05). Furthermore, WC skiers showed 8% higher V(peak) (P<0.05), but did not differ from NC skiers in acceleration and maximal strength. WC skiers performed more low- and moderate-intensity endurance training and speed training (both P<0.05). The current results show that aerobic capacity, efficiency, and high speed capacity differentiate WC and NC sprint skiers and it is suggested that these variables determine sprint skiing performance.