VO2max Test Research Articles

Higher Drop in Speed during a Repeated Sprint Test in Soccer Players Reporting Former Hamstring Strain Injury.

Aim: Hamstring strain injury is common in soccer. The aim of this study was to evaluate the physical capacity of players who have and have not suffered from hamstring strain injury in a sample of semi-professional and professional Norwegian soccer players in order to evaluate characteristics and to identify possible indications of insufficient rehabilitation.Method: Seventy-five semi-professional and professional soccer players (19 ± 3 years) playing at the second and third level in the Norwegian league participated in the study. All players answered a questionnaire, including one question about hamstring strain injury (yes/no) during the previous 2 years. They also performed a 40 m maximal sprint test, a repeated sprint test (8 × 20 m), a countermovement jump, a maximal oxygen consumption (VO2max) test, strength tests and flexibility tests. Independent sample t-tests were used to evaluate differences in the physical capacity of the players who had suffered from hamstring strain injury and those who had not. Mixed between-within subject's analyses of variance was used to compare changes in speed during the repeated sprint test between groups.Results: Players who reported hamstring strain injury during the previous two years (16%) had a significantly higher drop in speed (0.07 vs. 0.02 s, p = 0.007) during the repeated sprint test, compared to players reporting no previous hamstring strain injury. In addition, there was a significant interaction (groups × time) (F = 3.22, p = 0.002), showing that speed in the two groups changed differently during the repeated sprint test. There were no significant differences in relations to age, weight, height, body fat, linear speed, countermovement jump height, leg strength, VO2max, or hamstring flexibility between the groups.Conclusion: Soccer players who reported hamstring strain injury during the previous 2 years showed significant higher drop in speed during the repeated sprint test compared to players with no hamstring strain injury. The maximal speed, leg strength, ability to produce maximal power, endurance capacity, and hamstring flexibility was similar for both groups. Thus, a repeated sprint test consisting of 8 × 20 m could be used as a field-based diagnostic tool to identify players in need of reconditioning programs to ensure complete post-injury rehabilitation.

Does High Intensity Interval Training Improve Aerobic Power Development More Than Endurance Training?

The purpose of this study was to determine whether high intensity interval training (HIIT) increases VO2 max more so than to endurance training (ET). It is hypothesized that at the end of a 4-week training program, the HIIT group will have a higher average improved VO2 max percentage than the ET group. Recruited participants, 12 males, aged 18-35 completed a baseline VO2 max test followed by an intervention and then a post VO2 max test. Participants were randomly assigned to either HIIT or ET, 20 minutes a day, 3 times a week for 4 weeks. At baseline mean VO2 max for ET (n=6) was 48.2 ml/min/kg compared to a mean VO2 max of 51.7ml/min/kg in the HIIT (n=6) group. Post training test VO2 max for ET (n=6) was 48.9ml/min/kg compared to a mean VO2 max of 52.4ml/min/kg in the HIIT group (n=4). There was a 3.4% improvement in VO2 max in the HIIT group (n=4), while the ET group (n=6) had a 1.7% improvement in VO2 max. There were no significant differences (p>0.05) in height, weight, age, and VO2 max between the two groups in the baseline or post test. There were no significant differences in height, age, and VO2 max for either of the groups from the post test compared to the baseline test. Moreover, there were no significant differences in height, age, and VO2 max for either of the groups from the post-test compared to the baseline test. The data suggests a promising trend that HIIT training may be better for improving aerobic power than ET.

Effect of aquatic versus land based exercise programs on physical performance in severely burned patients: a randomized controlled trial.

[Purpose] To compare the effect of an aquatic-based versus a land-based exercise regimen on the physical performance of severely burned patients. [Subjects and Methods] Forty patients suffering from severe burn (total body surface area more than 30%) were recruited from several outpatient clinics in Greater Cairo. Their ages ranged between 20 to 40 years and were randomly assigned into two equal groups: group (A), which received an aquatic based exercise program, and group (B), which received a land-based exercise program. The exercise program, which took place in 12 consecutive weeks, consisted of flexibility, endurance, and lower and upper body training. Physical performance was assessed using 30 seconds chair stand test, stair climb test, 30 meter fast paced walk test, time up and go test, 6-minute walk test and a VO2max evaluation. [Results] Significantly increase in the 30 second chair stand, 6-minute walk, 30 meter fast paced walk, stair climb, and VO2 max tests and significantly decrease in the time up and go test in group A (aquatic based exercise) compared with group B (a land-based exercise) at the post treatment. [Conclusion] Twelve-week program of an aquatic program yields improvement in both physical performance and VO2 max in patients with severe burns.

Ergospirometry with concurrent fibre optic laryngoscopy: a randomised crossover study

ABSTRACT Background: Patients suffering from exercise-induced laryngeal obstruction (EILO) are subjected to several exhausting tests. We aimed to assess the feasibility of using a single test to obtain diagnostic measurements for maximum oxygen uptake (VO2max) and exercise-induced laryngeal obstruction (EILO). Methods: Patients referred to the outpatient respiratory clinic at the University Hospital of Bispebjerg, Copenhagen with exercise-induced dyspnoea were evaluated for inclusion over 13 months. Eligible patients were aged 18–43 years, had a known EILO diagnosis (moderate or severe) and were inactive (self-reported activity) with less than 3 hours activity per week. In randomised order, all participants (n = 11) underwent three tests: a VO2max test with and without concurrent laryngoscopy. VO2max and EILO values from the two testing methods were compared. Findings: There was no difference in VO2max measured by ergospirometry with and without simultaneous continuous laryngoscopy during exercise (CLE) testing (mean difference −22 ml O2･min−1; 95% CI −125 to 81 ml O2･min−1; P = 0.647). EILO scores obtained during the CLE testing on the treadmill versus CLE testing on the ergometer bike revealed identical supraglottic scores in nine of the 11 participants (82%) with substantial agreement between the two types of test (x = 0.71). Glottic scores were identical in six of the 11 (55%), showing moderate agreement between test types (x = 0.38). Conclusions: Based on our findings in inactive individuals, ergospirometry with laryngoscopy is feasible and well tolerated, yielding measurements for maximal oxygen uptake comparable to those of standard bike ergospirometry. Likewise, measurements of supraglottic EILO are comparable to those of the standard treadmill CLE test.

Energy systems efficiency influences the results of 2,000 m race simulation among elite rowers.

HypothesisEnergy efficiency within an elite group of athletes will ensure metabolic adaptation during training.ObjectivesTo identify energy system efficiency and contribution according to exercise intensity, and performance obtained during a 2,000 m race simulation in an elite group of rowers.MethodAn observational cross-sectional study was conducted in February 2016 in Bucharest, Romania, on a group of 16 elite rowers. Measurements were performed through Cosmed Quark CPET equipment, and Concept 2 ergometer, by conducting a VO2max test over a standard rowing distance of 2,000 m. The analyzed parameters during the test were: HR (bpm), Rf (b/min), VE (l/min), VO2 (ml/min), VCO2 (ml/min), VT (l), O2exp (ml), CO2exp (ml), RER, PaCO2 (mmHg), PaO2 (mmHg), Kcal/min, FAT (g), CHO (g), from which we determined the ventilatory thresholds, and the energy resource used during the specific 2,000 m rowing distance (ATP, ATP+CP, muscle glycogen).ResultsWe performed an association between HR (180.2±4.80 b/min), and carbohydrate consumption during the sustained effort (41.55±3.99 g) towards determining the energy systems involved: ATP (3.49±1.55%), ATP+CP (18.06±2.99%), muscle glycogen (77.9±3.39%). As a result, completion time (366.3±10.25 s) was significantly correlated with both Rf (p=0.0024), and VO2 (p=0.0166) being also pointed out that ≥5 l VO2 value is associated with an effort time of ≤360 s. (p=0.040, RR=3.50, CI95%=1.02 to 11.96). Thus, the average activation time among muscle ATP (12.81±5.70 s), ATP+CP (66.04±10.17 s, and muscle glycogen (295±9.5 s) are interrelated, and significantly correlated with respiratory parameters.ConclusionsDecreased total activity time was associated with accessing primary energy source in less time, during effort, improving the body energy power. Its effectiveness was recorded by early carbohydrates access, as a primary energy source, during specific activity performed up to 366 seconds.

Human runners exhibit a least variable gait speed

ABSTRACTThis study characterises the relationship between gait variability and speed in runners using data from trunk accelerations in each axis.Twelve participants of varying fitness ran on the treadmill with three sessions of six randomly ordered self-selected speeds. A VO2max test was conducted on the fourth session. Running gait was tracked with inertial sensors. The occurrence of a mid-range speed was analysed for the anterior–posterior, vertical and lateral directional coefficient of variation (CV) of root mean square (RMS) acceleration data.One participant with noisy gait signals was omitted. The results show all remaining participants consistently showed significant quadratic U-shaped relationships between vertical RMS CV acceleration and speed. Neither anterior–posterior nor lateral RMS CV acceleration were clearly related to speed. These least variable gait speeds were similar to estimates of optimal speed derived from minimum cost of transport with speed.In conclusion, there exists a mid-range speed for each runner with the least variable gait in the vertical direction, and this occurred significantly more often than would be expected by chance (P < 0.05). However, there are no prominent patterns for the anterior–posterior and lateral directions. This finding supports anecdotal evidence from runners and coaches concerning gait consistency.

Elevated salivary IgA, decreased anxiety, and an altered oral microbiota are associated with active participation on an undergraduate athletic team

BackgroundPrevious reports indicate that regular, but not excessive, exercise can moderate the response to anxiety and alter the immune response, therefore we hypothesized that college student athletes who were actively participating on an NCAA Division III athletics team (“in-season”) would have lower levels of anxiety and higher salivary IgA levels than similar college athletes who were in their “off-season”. NCAA Division III athletes participate in athletics at a level of intensity that is more moderate compared to other NCAA divisions. Alterations in the microbiome have been associated with alterations in psychosocial well-being and with exercise. Therefore, we also proposed that the oral microbiota would be different in “in-season” versus “off-season” athletes. MethodIn this pilot study, nineteen female students participating on a NCAA Division III athletic team (hockey=“in-season”; soccer=“off-season”) were compared for level of fitness (modified Balke test of VO2 max), salivary IgA levels by immunoassay, anxiety (using a GAD-7 survey), salivary cortisol levels by immunoassay, and numbers of culturable bacteria by growth of CFU/ml on blood agar, mitis salivarius agar and Staphylococcus 110 agar. ResultsThe proportion of subjects reporting “severe anxiety” on an anxiety scale (GAD-7) were significantly greater in the “off-season” group compared to the “in-season” group (p=0.047, Chi-squared test). “In-season” athletes had significantly higher salivary IgA/total protein levels than “off-season” athletes (one-sided Student's t-test; p=0.03). Cortisol levels were not significantly different in the two groups. The total culturable bacteria counts were higher among “in-season” athletes (p=0.0455, Wilcoxon Rank Sum test), as measured by CFUs on blood agar plates, an estimate of total culturable bacteria, including pathogenic and non-pathogenic bacteria. In contrast, there was a decrease in the growth of bacteria from the oral cavity of the “in-season” athletes, when the growth of bacteria on mitis salivarius agar (primarily oral streptococcus) was measured (p=0.0006, Wilcoxon Rank Sum test). There was a negative correlation (Spearman Rank correlation coefficient=−0.651, p=0.0018 one-sided) between high IgA levels and the growth of bacteria on mitis salivarius agar in the combined group of “in-season” and “off-season” athletes, suggesting a protective response of high IgA levels to the typical oral pathogenic bacteria. Anxiety levels (GAD-7) in the “in-season” group were positively correlated with growth of oral bacteria on blood agar (Spearman Rank correlation coefficient of 0.622 for “in-season”, p value=0.033 one-sided) and mitis salivarius agar (Spearman Rank correlation coefficient=0.671 for “in-season, p value=0.021 one-sided), and negatively correlated in “off-season” athletes on blood agar (−0.689 for “off-season”, p value=0.028 one-sided), supporting the hypothesis that the microbiota are distinct in “in-season” and “off-season” athletes and may be associated with anxiety levels. ConclusionThese findings are supportive of the hypothesis that participation in college level athletics has a positive effect on student-athlete health, specifically enhanced protective oral immunity, reduced anxiety, and alterations in oral microbial populations.

Applicability of an Indirect VO2max Test: Its Association with the 400 Meters Freestyle Performance

The aim of this study was to evaluate the VO2max using a previously validated indirect test for non-expert adult swimmers and to verify its connection with the 400 meters freestyle test. A total of 17 non-expert male swimmers (21.5 ± 3.12 years) were evaluated. Body composition measurements included body weight (74 ± 9.41 kg), height (172.9 ± 5.21 cm) and body fat percentage (15.2 ± 4.15 %). Two tests were conducted on different days; the 400 meters freestyle (400 MF) and the Progressive Swim Test (PSwT), respectively. The participant's heart rate frequency before and after the test (BHR and AHR) was analyzed, as well as the subjective perception of effort (RPE), the number of laps covered (NLP), and the time of test execution measured in minutes. Significant differences were identified in all variables (p - 0.60) was found between AHR and execution time (r > - 0.70), as well as between the VO2max estimated by the PSwT and the 400 MF performance test (r > - 0.70). The Bland-Altman Plot showed that the values discovered were within the established concordance limits of 95% (±1.96 SD). A negative correlation between a swimming test and a test that estimates the VO2max occurred, and the PSwT showed results of greater approximation of the aerobic power of non-expert swimmers. In conclusion, the PSwT is applicable for non-expert adult swimmers.

Cardiorespiratory Fitness and Peak Torque Differences between Vegetarian and Omnivore Endurance Athletes: A Cross-Sectional Study.

In spite of well-documented health benefits of vegetarian diets, less is known regarding the effects of these diets on athletic performance. In this cross-sectional study, we compared elite vegetarian and omnivore adult endurance athletes for maximal oxygen uptake (VO2 max) and strength. Twenty-seven vegetarian (VEG) and 43 omnivore (OMN) athletes were evaluated using VO2 max testing on the treadmill, and strength assessment using a dynamometer to determine peak torque for leg extensions. Dietary data were assessed using detailed seven-day food logs. Although total protein intake was lower among vegetarians in comparison to omnivores, protein intake as a function of body mass did not differ by group (1.2 ± 0.3 and 1.4 ± 0.5 g/kg body mass for VEG and OMN respectively, p = 0.220). VO2 max differed for females by diet group (53.0 ± 6.9 and 47.1 ± 8.6 mL/kg/min for VEG and OMN respectively, p < 0.05) but not for males (62.6 ± 15.4 and 55.7 ± 8.4 mL/kg/min respectively). Peak torque did not differ significantly between diet groups. Results from this study indicate that vegetarian endurance athletes’ cardiorespiratory fitness was greater than that for their omnivorous counterparts, but that peak torque did not differ between diet groups. These data suggest that vegetarian diets do not compromise performance outcomes and may facilitate aerobic capacity in athletes.

High-intensity interval training (HIIT) or miss: is HIIT the way forward for obese children?

A lack of time is often cited as a reason for no improvement in physical activity rates. Danielle Lambrick of the University of Southampton, Lee Stoner of Massey University, New Zealand, and James Faulkner of the University of Winchester consider how high-intensity interval training (HIIT) may address this problem for children .Globally, there is a continual increase in the prevalence of childhood obesity,[1] placing children at increased risk for premature onset of non-communicable diseases (NCDs), including musculoskeletal disorders, some cancers, and cardio-metabolic diseases such as type 2 diabetes and cardiovascular diseases (CVD).[1] This rise in obesity and co-morbid complications has been strongly linked to lifestyle choices, including physical inactivity.[2] However, despite heightened public awareness of the relationship between physical inactivity and obesity, rates of physical activity are not improving.[3] An often cited barrier to physical activity among both adults and children is a lack of time,[4] which has led to the promotion of high-intensity interval training (HIIT) as a more time-efficient exercise prescription strategy.A recent meta-analysis by Garcia-Hermoso et al.[4] has examined the limited number of studies investigating the efficacy of HIIT in overweight and obese youth. HIIT was not reported to be superior to other forms of exercise when examining changes in body composition, but it was suggested to be more effective for improving systolic blood pressure (SBP) and cardio-respiratory fitness. These findings indicate that HIIT may be effective for improving cardio-metabolic health and thus, decreasing the risk of NCDs. However, these physiological findings need to be considered in the context of clinical inference, implementation science, and the potential for public health outcomes.Clinical InferencePrior to discussing the implementation of HIIT, the potential clinical implications should be contextualised. As a primary outcome, the meta-analysis by Garcia-Hermoso et al.[4] utilised the gold-standard measure of cardio-respiratory fitness: maximal oxygen uptake (VO2 max). When compared to other forms of exercise, VO2 max improved, on average, by 1.92 mL kg-1 min-1 . While findings in children are inconclusive,[5],[6] cardio-respiratory fitness has been recognised as a more important correlate of cardio-metabolic health than obesity in adults.[7] However, 1.92 mL kg-1 min-1 is greater than the measurement error for VO2 max testing and it is thus unlikely that such a small change is clinically meaningful in terms of risk stratification.Garcia-Hermoso et al.[4] also reported that SBP improved, on average, by 3.67 mmHg. High SBP (hypertension) is associated with earlier onset of CVD[8] and, according to the World Health Organization (WHO), is likely the leading risk factor for death worldwide.[9] While child-specific data are unavailable, in adults, a 20-mmHg increase in SBP is associated with a two-fold increase in risk of death from coronary artery disease or stroke.[10] However, a value of 3.67 mmHg is greater than the measurement error of most blood pressure devices,[11] and it is difficult to discern the clinical importance of such a small change. The authors do also report on several markers of body composition, blood lipids, and insulin resistance, none of which were found to be statistically different or clinically meaningful. Nonetheless, HIIT has been reported to result in clinically meaningful improvements in cardiovascular health among adults,[12] so this form of exercise prescription does hold potential, and discussion is warranted in terms of implementation and public health outcomes. …

Maintaining a clinical weight loss after intensive lifestyle intervention is the key to cardiometabolic health

Intensive lifestyle interventions (ILI) are criticised for ineffective obesity treatment because weight loss over time is modest and thus of limited clinical relevance. However, a subgroup (5-30%) maintains a clinical weight loss >10%, but it is not clear if cardiometabolic health follows this pattern. The aim was to study the effect of different magnitudes of weight loss maintenance after ILI on cardiometabolic health. Eighty out of 2420 former participants (age: 36±1, BMI: 38±1, (means ±SE)) in an 11-12-week ILI were recruited into 3 groups; clinical weight loss maintenance (>10% weight loss), moderate maintenance (1-10%), and weight regain based on weight loss at follow-up (5.3±0.4years). Weight loss during the ILI was achieved by increased physical activity and hypo-caloric diet. Dual X-ray Absorptiometry, blood sample, skeletal muscle biopsy and VO2max test were used to determine cardiometabolic health at follow-up. At follow-up, the clinical weight loss maintenance group scored better in the following variables compared to the other groups: BMI (31±1, 33±2, 43±2kg/m2), composition (34±2, 40±1, 49±1% fat), visceral adipose tissue (0.8±0.2, 1.7±0.5, 2.4±0.4kg), plasma triglycerides (0.8±0.2, 1.3±0.4, 1.6±0.3mmol/L), plasma glucose (4.9±0.1, 5.9±0.4, 5.9±0.1mmol/L), Hb1Ac (5.1±0.0, 5.6±0.2, 5.8±0.2%), protein content in skeletal muscle of GLUT4 (1.5±0.2, 0.9±0.1, 1.0±0.1 AU) and hexokinase II (1.6±0.2, 1.0±0.2, 0.7±0.1 AU), citrate synthase activity (155±6, 130±5, 113±5μmol/g/min) and VO2max (49±1, 43±1, 41±1mL/min/FFM) (p<0.05). Cardiometabolic health is better in participants who have maintained >10% weight loss compared to moderate weight loss and weight regain.

The Effect of Aging on Relationships between Lean Body Mass and VO2max in Rowers.

Aging is associated with a fall in maximal aerobic capacity as well as with a decline in lean body mass. The purpose of the study was to investigate the influence of aging on the relationship between aerobic capacity and lean body mass in subjects that chronically train both their upper and lower bodies. Eleven older rowers (58±5 yrs) and 11 younger rowers (27±4 yrs) participated in the study. Prior to the VO2max testing, subjects underwent a dual energy X-ray absorptiometry scan to estimate total lean body mass. Subsequently, VO2max was quantified during a maximal exercise test on a rowing ergometer as well as a semi-recumbent cycle ergometer. The test protocol included a pre-exercise stage followed by incremental exercise until VO2max was reached. The order of exercise modes was randomized and there was a wash-out period between the two tests. Oxygen uptake was obtained via a breath-by-breath metabolic cart (Vmax™ Encore, San Diego, CA). Rowing VO2max was higher than cycling VO2max in both groups (p<0.05). Older subjects had less of an increase in VO2max from cycling to rowing (p<0.05). There was a significant relationship between muscle mass and VO2max for both groups (p<0.05). After correcting for muscle mass, the difference in cycling VO2max between groups disappeared (p>0.05), however, older subjects still demonstrated a lower rowing VO2max relative to younger subjects (p<0.05). Muscle mass is associated with the VO2max obtained, however, it appears that VO2max in older subjects may be less influenced by muscle mass than in younger subjects.

Growth hormone (GH) enhances anaerobic capacity: impact on physical function and quality of life in adults with GH deficiency.

Anaerobic capacity is impaired in adults with GH deficiency (GHD), adversely affecting physical function and quality of life (QoL). To investigate whether GH replacement improves anaerobic capacity, physical function and QoL in adults with GHD. One-month double-blind placebo-controlled crossover study of GH (0·5mg/day), followed by a 6-month open phase. A total of 18 adults with GHD. Anaerobic power (watts) was assessed by the 30-s Wingate test, and aerobic capacity by the VO2 max (l/min) test. Physical functional was assessed by the stair climb test, chair stand test, 7-day pedometry and QoL by the AGHDA questionnaire. Lean body mass (LBM) was quantified by dual-energy X-ray absorptiometry. GH replacement normalized IGF-1 levels during both study phases. During the 1-month placebo-controlled study, improvement in stair climb and chair stand performance was observed during GH and placebo treatment; however, there were no significant GH effects observed in any outcome measure compared to placebo. Six months of GH treatment significantly increased anaerobic power (P<0·05), chair stand repetitions (P<0·0001), daily step count (P<0·05) and QoL scores (P<0·001) compared to baseline measurements. GH treatment did not significantly improve VO2 max. Improvement in anaerobic power independently predicted an improvement in energy and vitality domain of QoL (P=0·03). GH replacement improves anaerobic capacity, physical function and QoL in a time-dependent manner in adults with GHD. Improvement in the anaerobic but not aerobic energy system is likely to underlie the improvement in QoL in patients with GHD during GH replacement.

Perbandingan pemberian air kelapa muda (cocos nucifera l) dengan isotonik terhadap denyut nadi dan VO2maks atlet remaja

Background: Football players requires a high level of VO2max which is influenced by the available of energy. Tender coconut water and branded isotonic are as energy drinks containing of carbohydrates and the body’s electrolyte ions that can prevent dehydration. The increasing pulse describes a the condition of dehydrated players during match or training. Objective: To Examine comparison of tender hybrid coconut water and branded isotonic to pulse and the plyer’s level of VO2max in the Diponegoro University Football School in Tembalang, Semarang. Methods: Experimental study with an approach of randomized pretest - post test control group design at 41 soccer’s player aged 13-15 years at Diponegoro University Football School Tembalang in August 2015. The treatment group consumed consumed 250 mL tender coconut water (n=13) and branded isotonic (n=14) and group control consumed mineral water (n=14) every 15-30 minutes for 5 times. Observation pre test and post test 1,2,3 with interval of 3 day after physical training, athlets test the pulse to palpation techniques for 15 seconds and VO2max test with multistage fitness test. Result: The VO2max and pulse recovery in the beginning of research for 3 group was similar (p = 0,454 and p = 0,294). Post test 1 VO2max on three group are same (p = 0,841) but the recovery pulse is better on the group of tender coconut water and branded isotonic (p = 0.006). Post test 2, VO2max and recovery pulse is more good by players who were given tender hybrid coconut water and branded isotonic (p = 0,004 and p = 0,017), as the same post test 3 VO2max and recovery pulse (p = 0.000 and p = 0,004).Conclusion: Giving the tender hybrid coconut water and branded isotonic to same to recovery pulse and increased VO2maks on athlete school football diponegoro unversity

The effect of trial familiarisation on the validity and reproducibility of a field-based self-paced VO2max test.

The self-paced maximal oxygen uptake (VO2max) test (SPV), which is based on the Borg 6-20 Ratings of Perceived Exertion (RPE) scale, allows participants to self-regulate their exercise intensity during a closed-loop incremental maximal exercise test. As previous research has assessed the utility of the SPV test within laboratory conditions, the purpose to this study was to assess the effect of trial familiarisation on the validity and reproducibility of a field-based, SPV test. In a cross-sectional study, fifteen men completed one laboratory-based graded exercise test (GXT) and three field-based SPV tests. The GXT was continuous and incremental until the attainment of VO2max. The SPV, which was completed on an outdoor 400m athletic track, consisted of five x 2 min perceptually-regulated (RPE11, 13, 15, 17 and 20) stages of incremental exercise. There were no differences in the VO2max reported between the GXT (63.5±10.1 ml·kg-1·min-1) and each SPV test (65.5±8.7, 65.4±7.0 and 66.7±7.7 ml·kg-1·min-1 for SPV1, SPV2 and SPV3, respectively; P>.05). Similar findings were observed when comparing VO2max between SPV tests (P>.05). High intraclass correlation coefficients were reported between the GXT and the SPV, and between each SPV test (≥.80). Although participants ran faster and further during SPV3, a similar pacing strategy was implemented during all tests. This study demonstrated that a field-based SPV is a valid and reliable VO2max test. As trial familiarisation did not moderate VO2max values from the SPV, the application of a single SPV test is an appropriate stand-alone protocol for gauging VO2max.

Test Preference and its Relationship to Performance during Maximal Aerobic Exercise Testing

Maximal aerobic capacity (VO2max) is a strong variable in predicting risk of death from all-cause mortality as well as performance in many endurance sports. Proper test selection is important, and test preference may affect the results of VO2max testing. PURPOSE: To compare the preferred test method between three different VO2max tests and determine the relationship to performance. METHODS: 13 active subjects (8 men, 5 women; age 24±3 yrs) volunteered to participate in this study. All underwent three tests including: a standard Bruce protocol treadmill test followed by, in random order, a self-paced maximal VO2max test (SPV) on a cycle ergometer (CE SPV) and a treadmill (TM SPV). The SPVs were ten minutes long with intensity increasing every two minutes based on the 6-20 Rating of Perceived Exertion (RPE) scale, and included RPE values of 11,13,15,17 & 20. With the SPVs, subjects controlled the work rate to maintain the prescribed RPE. After the last test, subjects were immediately asked which test they preferred of the three, without further instruction. A chi-square goodness of fit was performed to determine if the tests were equally preferred and a chi-square test of independence was used to examine the relationship between preference and performance. RESULTS: Of the 13 subjects, five preferred the TM SPV (38%), six preferred the CE SPV (46%), and two preferred the Bruce protocol treadmill test (16%). Preference was equally distributed (X2=2.000, p=.368). Eight of the subjects (62%) preferred the test they performed their best on while five did not (38%). The relationship between test preference and performance was not significant (X2=8.790, p=.067). CONCLUSIONS: In this study, “preference” was not defined for the subjects. Some may have chosen their preferred test based on which one they thought they would perform best. These tests are maximal and thus subjects usually discontinue their efforts due to signals of overall or peripheral discomfort. The preferred test may have been chosen based solely on the level of discomfort experienced. Regardless, the results suggest that test preference may not affect performance during VO2max testing. Future studies should seek to examine how subjects define “preference” and if it could be used to choose the most appropriate protocol.

Effect of Acute Exercise on Mood and Cardiovascular Variables between Normoxia and Normobaric Hypoxia

Exposure to hypoxic environments can have profound deteriorating effect on physiologic and cognitive abilities, this can be observed with decreased mood, impaired judgement and reduced reaction time. Recently, studies have reported that acute moderate exercise has a positive effect on cognition and mood in persons in normoxic conditions. Collectively, acute physiological changes resulting from moderate exercise may improve mood and cognition at altitude. PURPOSE: The purpose of this study was to determine differences in anxiety, fatigue and vigor when acute moderate exercise was performed in a normobaric hypoxic (NH) and normoxic (N) environment. To help quantify these changes, arterial oxygen saturation (SaO2), heart rate (HR) and blood pressure (BP) were also collected. METHODS: Nine (four women and five men) young, healthy participants completed a submaximal cycling protocol of four minute stages at 40, 80, and 120 watts. Following the submaximal protocol, a VO2 max test was completed to determine each participant’s cycling power that would elicit 60% of their max in subsequent visits. The VO2 max tests were completed in both (N) and hypoxia (NH). In both the N and NH conditions, baseline SaO2, HR, BP, anxiety, fatigue, and vigor values were collected and the participants spent 30 minutes acclimating before beginning exercise. The participant then cycled for 20 minutes and data was collected during the final 5 minutes of cycling. Data was collected again at 1, 15, 30, and 45 minutes after exercise. The order of conditions (N and NH) was counterbalanced. RESULTS: There was a main effect of condition, F (6) = 40.30, p = 0.000, time, F (1) = 284.08, p = 0.000, as well as an interaction between condition and time, F (6) = 20.81, p = 0.000, in SaO2. There was a main effect of time, F (6) = 51.02, p = 0.000, and an interaction, F (6) = 3.56, p = 0.005, in HR. Over time, SaO2 decreased and HR increased in the NH condition. There were no significant effects (P > 0.05) found for anxiety, fatigue, vigor, heart rate, and blood pressure. CONCLUSIONS: An acute bout of exercise has no effect on anxiety and fatigue in a hypoxic condition. However, an acute bout of exercise has a positive effect on vigor in NH. Future studies could examine the effect of graded exercise intensities and different exercise modalities on mood state in hypoxia.

Body Protein Retention is Maintained in Older Adults Performing High-Intensity Interval Training (HIIT)

High-intensity interval training (HIIT) is a popular and effective program to elicit physiologic adaptations favorable to quality of life improvement and metabolic disease risk reduction. Whether an older population (>50 y) would be more challenged to retain body protein performing HIIT compared to younger individuals is unknown. PURPOSE: To determine if measures of body protein retention and exercise performance change in older adults completing a 2-week HIIT program, compared to younger adults. METHODS: Healthy, young (n=8; 24.4±3.6 y; BMI=27.1±2.8 kg·m-2) and older (n=8; 59.4±5.6 y; BMI=26.8±5.6 kg·m-2) males and females completed a 2-week (6 sessions) HIIT program on a cycle ergometer. Baseline nitrogen balance (NBAL) and urinary creatinine (UC) were assessed from 24-h urine collection and 3-d habitual diet recall. Baseline maximal oxygen uptake was determined via graded exercise test with indirect calorimetry on a cycle ergometer. Each HIIT session was 10x60 s at 90% of peak power achieved in the VO2max test. Recovery interval was 60 s active recovery (50 W). Nitrogen balance and urinary creatinine were determined on the initial and final (6th) day of the HIIT program by 24-h urine collection and a prescribed, eucaloric, adequate-protein diet (1.5 g protein·kg-1·d-1 and ≤ 30% of kcal from lipid.) A final VO2max test was used to assess changes in peak oxygen uptake (VO2) and peak power (PP). RESULTS: RMANOVA resulted in no significant mean difference in NBAL, UC, VO2, and PP between baseline, initial and final workout days in the young and older groups (p<0.05; see table). CONCLUSION: Older, healthy adults can retain body protein while engaging in HIIT as long as they consume a eucaloric diet with adequate dietary protein (1.5 g·kg-1·d-1).Table: No title available.

Effects of Whole Body Periodic Acceleration on Blood Lactate and Recovery Following Maximal Exercise

PURPOSE: Whole-body Periodic Acceleration (WBPA) is a mechanical bed that moves cyclically in a head to foot motion and has been shown to improve blood flow through increasing endothelial-released nitric oxide. This may improve circulation and improve clearance of metabolites. We examined if WBPA may be an effective method of recovery after maximal exercise compared to the gold standard of active recovery following maximal exercise. METHODS: 10 subjects (age 242.2, male n= 6, female n=4), performed a VO2max test using a Bruce protocol and then immediately participated in a recovery protocol using either WBPA or walking (2.0 mph) for 20 minutes. Subjects returned on another day to repeat the VO2max test and perform the other recovery protocol. Outcome measures were blood lactate concentration (BL), heart rate (HR), blood pressure (BP) and oxygen consumption (VO2). These markers were measured at rest, exhaustion, and minutes 1, 4, 7, 10 and 20 of the recovery protocols. Independant t-tests and post hoc Bonferroni were used to compare outcome measures of the recovery protocols. RESULTS: No significant difference was found in BL between recovery protocols. VO2 (ml/kg/min) was significantly lower (P<0.05) for WPBA compared to walking at minutes 4 (8.293.59 vs. 11.273.50), 7 (5.712.88 vs. 9.732.46) and 10 (5.11.68 vs 9.212.60) of recovery. HR was significantly lower (P<0.05) for WBPA vs. walking at minutes 4 (106.59.98 vs 123.2514.76), 7 (103.2511.15 vs. 116.7112.91), 10 (99.7512.57 vs. 118.1414.99) and 20 (94.1312.26 vs. 111.1317.76). CONCLUSION: Our pilot data suggests that WBPA may reduce HR and VO2 faster than walking in the first 10 minutes of maximal exercise recovery.

The Effects of Peppermint Oil on the Ventilatory Threshold of Endurance-Trained and Moderately Active Men

Peppermint oil (mentha piperita) has been shown to have cooling effects in animals and humans, as well as beneficial influences on pulmonary function tests possibly due to bronchodilatory mechanisms. PURPOSE:To determine whether a single supplementation of one milliliter of peppermint oil would raise the ventilatory threshold in endurance-trained and moderately active men. METHODS:Six male participants (3 endurance-trained, 3 moderately active) performed two maximal oxygen consumption (VO2max) tests on a cycle ergometer under randomized, single-blind trials of peppermint oil and placebo. For each exercise test, ventilatory threshold was determined through the ventilatory equivalent method (VE/VO2 and VE/VCO2 vs. time), ventilation method (VE vs. time), and the VCO2 vs. VO2 method to validate the point at which the ventilatory threshold occurred. RESULTS:Supplementation of peppermint oil resulted in the ventilatory threshold occurring at a significantly higher percentage of VO2max compared to placebo (71 ± 2 % of VO2max vs. 65 ± 2 % of VO2max, p < .05). Additionally, VO2max values were not different between the two conditions. CONCLUSIONS:Peppermint oil supplementation may have a positive impact on the ventilatory threshold of both endurance-trained and moderately active men by raising the percentage of VO2max at which the ventilatory threshold occurs. Though further research is needed to determine the mechanism, it appears that the cooling and the smooth muscle relaxing properties of peppermint oil may acutely contribute to improved aerobic performance.