Age-predicted Maximum Heart Rate Research Articles

Aerobic and Anaerobic Fitness Levels of Pre-Professional Contemporary Dancers: An Exploration of 2 Dance-Specific Field Tests.

The primary aim of this study was to present descriptive heart rate (HR), heart rate recovery (HRR) and RPE data for the DAFT and HIDT within one sample of contemporary dance students. The second aim was to explore if objective (HR) and subjective (RPE) data were correlated between tests. 40 (11 males, 29 females) university dance students with a mean age of 18.8 ± 1.8 years performed the DAFT and HIDT on 2 separate occasions within 1 week. Measurements were HR after 4 minutes in all stages of the DAFT, the percentage of age-predicted maximal HR (%HRmax) of all stages of the DAFT and at the end of the HIDT, and peak HR (HRpeak) at the end of both tests. Subjective ratings of perceived exertion (RPE) and HR recovery after 1 minute of rest (HRR) were determined after the tests. HRpeak of the DAFT and HIDT were 188.1 ± 11.0 and 185.3 ± 7.3 beats·min-1, respectively. There were high positive correlations between HRpeak of the HIDT and stages 3 to 5 of the DAFT (r = 0.716-0.740, all P-values < .01). HRR (r = .678, P < .01) and %HRmax (r = .746, P < .01) showed moderate to high correlations between the DAFT and HIDT. The anaerobic training zone was reached in stages 4 and 5 of the DAFT and at the end of the HIDT. The subjective RPE scores did not significantly correlate between DAFT and HIDT, neither with objective HR data. Although the DAFT and HIDT differ in intensity and work-to-rest ratio, there were high correlations between HR and HRR data of both tests and both tests reached intensities above the anaerobic threshold (%HRmax > 85%).

Does mild chronic obstructive pulmonary disease need a standard pulmonary rehabilitation program? A case report

Background: Patients with mild chronic obstructive pulmonary disease (COPD) are usually not recommended for a standard pulmonary rehabilitation (PR)program based on the GOLD guideline in mild COPD GOLD A classification. Especially, the scientific evidence on exercise capacity that can be identified for recruitment in PR programs has been less reported. Thus, a preliminary case study to identify the exercise capacity under cardiopulmonary responses by aerobic exercise testing among patients in mild COPD GOLD A classification was the aim of this study. Objective: To evaluate the cardiopulmonary responses from exercise capacity testing in individual COPD patients with mild COPD GOLD A Classification. Materials and methods: Four participants with mild COPD GOLD A performed an exercise endurance capacity test at home using Spot Marching Exercise Test (SMT), marching on the spot with high hip and arm raising. The load of SMT was indicated by a controlled stepping rate at 70, 80, 90, 100, and 110 steps/min. Every participant performed Incremental SMT (ISMT) with every 3 min incremental load, and the Constant SMT (CSMT) at the peak load. Both exercise tests were terminated at symptom limit. Resting time between ISMT and CSMT was at least 30 minutes. Cardiopulmonary exercise responses, Borg perceived breathlessness (RPB) and exertion (RPE) were monitored every minute during the exercise test. The duration of exercises was recorded. Results: Peak exercise capacity using ISMT was low with the end exercise load at 70, 80, 80, and 90 steps/min which is equivalent to moderate to high intensity at 81%, 62%, 65% and 93% of age-predicted maximum heart rate (HRmax). The exercise test was stopped by breathlessness at RPB 7, 8, 6, and 5. Respiratory rates (RR) were 36, 26, 38, and 38 breaths/min. With CSMT, the results showed very short exercise duration 1.78, 4.60, 2.15, and 2.47 mins with RPB 7, 8, 5, and 5 and RR of 33, 27, 34, and 41 breaths/min respectively. Conclusion: This preliminary report reveals that all four mild COPD GOLD A show low exercise capacity and very poor exercise endurance that should identify the appropriated standard PR program in the future.

Myocardial Blood Flow in Newly Diagnosed Breast Cancer Patients at Rest and During Exercise

Heart depends critically on continuous supply of blood, but it is unknown whether cancer, without any treatments, affects myocardial blood flow (MBF) at rest or during exercise. This study therefore aimed at measuring MBF in cancer patients and control subjects and it was hypothesized that MBF is affected by cancer. The study included recently-diagnosed breast cancer patients (n=18) who had not started their oncologic treatments and age-matched female control participants (n=32). Controls were women referred to cardiac diagnostic testing but who were by this testing judged to be free of obstructive coronary artery disease. MBF was quantified with [15O]H2O positron emission tomography (PET) at rest in both groups and additionally during 10-min supine bicycling exercise in the breast cancer patients. Furthermore, cardiac morphological changes were analyzed with a breast cancer mice-model four weeks after the inoculation of 13TC mammary tumor cells. Respective mice without tumors served as controls. Resting heart rate (HR) and rate pressure product (RPP) correlated positively with resting MBF, but were similar in both groups resulting also in similar resting MBF in cancer patients and controls. MBF increased significantly from rest during exercise in breast cancer patients (p&lt;0.0001) and exercising MBF correlated positively with the histologic grade of cancer (r=0.54, p=0.021). However, cancer grade did not associate with exercise intensity measures such as HR, RPP or HR percentage from age-predicted maximal HR. In the mouse model, the breast cancer did not affect heart weight, cardiomyocyte size, myocardial capillary density, or capillary-to-myocyte size ratio. In conclusion, resting MBF in humans or myocardial capillarity in mice appear not to be affected by breast cancer. However, the more severe is the histologic grade of cancer, the higher is the MBF during exercise in patients with breast cancer, independently of the intensity of the exercise suggesting dysregulation of myocardial blood supply with cancer. This novel finding requires further investigations. This study was financially supported by Academy of Finland and Hospital District of South-West Finland. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Use of the Buffalo Concussion Treadmill Test in community adult patients with mild traumatic brain injury.

The Buffalo Concussion Treadmill Test (BCTT) is used to establish exercise tolerance for rehabilitation and identify injury subtypes for youth athletes after mild traumatic brain injury (mTBI). Its utility in adult community members is unknown. Primary: To describe how adults with and without mTBI tolerate the BCTT. Secondary: To explore relationships between baseline factors, mTBI-related symptoms, and BCTT duration. Prospective, observational, longitudinal. Academic medical center. Thirty-seven adults treated in a level 1 trauma center emergency department with mTBI; 24 uninjured controls (UC). N/A. Participants completed two visits 3 weeks apart (1 week and 1 month after mTBI) including a 15-minute BCTT, the Rivermead Post Concussion Symptoms Questionnaire (RPQ), and preinjury International Physical Activity Questionnaire. Analyses characterized BCTT response and associations between baseline factors, RPQ scores, and BCTT duration. Persons with mTBI discontinued earlier than UC at 1-week postinjury using standard discontinuation criteria for exercise intolerance. The percentage of mTBI participants with signs of possible mTBI-related intolerance was 55.6% at 1 week (36.1% for mTBI-related symptom exacerbation, 19.4% for exertion/fatigue before reaching 85% of one's age-predicted maximum heart rate [HR]) and 48.0% at 1 month (40.0% mTBI-related symptom exacerbation, 8.0% exertion without reaching the target HR). Thirty percent of UCs completed the BCTT at both assessments. UCs met discontinuation criteria for increased nonspecific symptoms (eg, pain/general discomfort and increased Visual Analog Scale ratings; 39-61%) and physical exertion (9-26%). Shorter duration was associated with higher body mass index (r = -0.42 - -0.45), shorter height (r = 0.22-0.29), female gender (r = -0.26 - -0.27), and greater RPQ symptoms (r = -0.28 - -0.47). The BCTT exacerbates mTBI-related symptoms in adult community members. Participant characteristics and noninjury factors influence performance. The findings imply the BCTT could be useful in clinical assessments of adults with mTBI. Interpretation should account for the unique characteristics of nonathletes.

Feasibility and Safety of Early Post-COVID-19 High-Intensity Gait Training: A Pilot Study.

The feasibility and safety of rehabilitation interventions for individuals recovering from COVID-19 after the acute stage is not well understood. This pilot study aims to provide a preliminary investigation of the feasibility and safety of providing high-intensity gait training (HIT) with a targeted cardiovascular intensity of 70-85% of the age-predicted maximum heart rate (HRmax) for individuals undergoing rehabilitation post-COVID-19. Consecutive patients who were medically cleared for HIT were invited to participate in the study. Participants practiced walking in varied contexts (treadmill, overground, and stairs), aiming to spend as much time as possible within their target cardiovascular intensity zone during scheduled physical therapy (PT) sessions. Training characteristics and adverse events were collected to determine the feasibility and safety of HIT. The severity of adverse events was graded on a 1-5 scale according to the Common Terminology Criteria for Adverse Events. The participants (n = 20) took a mean of 2093 (±619) steps per PT session. The average peak heart rate during PT sessions was 81.1% (±9.4) of HRmax, and 30.1% (±21.0) of the session time was spent at heart rates ≥ 70% HRmax. Mild adverse events (grade 1) occurred in <5% of the sessions, and no intervention-requiring or life-threatening adverse events (grade 2-5) occurred. This pilot study provides preliminary evidence that HIT may be feasible and safe during inpatient rehabilitation for patients post-COVID-19 following medical clearance.

FEASIBILITY OF AEROBIC FITNESS TESTING IN AMNESTIC MILD COGNITIVE IMPAIRMENT FROM THE ACT TRIAL

Abstract Aerobic fitness has been postulated as a physiological mechanism of action for aerobic exercise to modify Alzheimer’s disease, but it has not been adequately studied in older adults with (MCI). The purpose of this study is to evaluate the feasibility of a gold-standard, laboratory-based, symptom-limited cycle-ergometer exercise testing (GXT) in older adults with amnestic mild cognitive impairment (aMCI) to assess peak oxygen consumption (VO2max [ml/kg/min]) using baseline data from the ACT Trial. The test was categorized as a submax, near-max, and max test based on if 0, 1, and ≥2 of the American College of Sports Medicine criteria was met: &amp;gt;90% of age-predicted maximum heart rate, plateau in VO2Peak, respiratory exchange ratio &amp;gt;1.10, and rating of perceived exertion &amp;gt;17. VO2max was predicted as 3.5*maximal metabolic equivalents (METs). Among 146 enrolled participants (73.8±5.7 years old with 16.9±2.9 years of education, 51.4% men, and 91.8% Caucasian), 145 completed GXTs. Sixteen GXTs (11.0%) were submax (VO2Peak 13.5±4.4), 53 (36.6%) were near-max (VO2Peak 16.5±4.1), and 76 (52.4%) were max (VO2Peak 18.4±5.1). Predicted VO2max were 21.6±6.8, 28.7±26.3, and 30.0±20.5 from submax, near-max, and max tests, respectively. Among max GXTs, VO2max was 19.5±4.9 in men (n=37) and 17.4±5.1 in women (n=39). In conclusion, GXTs was feasible for ~52% of the participants. METs-based prediction overly inflates VO2max estimates, in comparison to VO2max obtained from max GXTs. VO2max levels are substantially lower in older adults with aMCI than peers (23.1±6.3 in men and 21.1±3.4 in women), suggesting aerobic exercise as an important intervention for this population.

Does Exercise Testing with Arm Crank Ergometer Substitute for Cycle Ergometer to Evaluate Exercise Capacity?

Using the upper limbs to test cardiopulmonary exercise can be a useful option in the case of individuals who are unable to pedal a bicycle due to lower limb injury or disability. We evaluated whether exercise testing with the upper limbs can be used equivalently to that of the lower limbs in assessing exercise capacity. Nine collegiate rowers and eight collegiate cyclists underwent incremental exercise testing with an arm crank ergometer (ACE) and cycle ergometer (CE). Heart rate (HR) and oxygen uptake (VO2) were monitored throughout the tests. Segmental muscle mass and flow-mediated dilation of brachial artery were measured to assess the training status of the upper limbs. The muscle mass of the brachium, upper limb, and trunk were greater in the rowers than in the cyclists (p &lt; 0.05). The correlations between HR and VO2 was significantly different depending on exercise modalities, ACE and CE, in both groups (p &lt; 0.001). The estimated maximal VO2 using the correlation formula and age-predicted maximal HR was significantly lower in the exercise testing group with ACE than in the group with CE in rowers and cyclists (41.7 ± 7.3 vs. 52.6 ± 8.6 mL/kg/min, p = 0.010 and 35.5 ± 14.2 vs. 50.4 ± 13.4 mL/kg/min, p = 0.011, respectively). The results suggested that exercise capacity assessed by exercise testing with ACE is underestimated, regardless of the training status of the upper limbs. Further research is needed to verify factors which affect the correlations between HR and VO2 during upper- and lower-limb exercise.

Comparison of VO2max Estimations for Maximal and Submaximal Exercise Tests in Apparently Healthy Adults.

Due to limited accessibility, direct measurement of VO2max is rarely performed in clinical settings or sports centers. As a result, regression equations have been developed and are currently used during exercise tests to provide an indirect estimation. The American College of Sports Medicine (ACSM) has recommended a regression equation for running to provide an indirect estimation of VO2. However, significant differences have been observed between these estimations and directly measured VO2max. Additionally, since submaximal assessments may be more convenient for both athletes and sedentary/diseased individuals, they were included in the analysis. This study aimed to evaluate the accuracy of VO2max estimations provided using the ACSM running equation when used during both maximal and submaximal exercise tests among adult runners. A total of 99 apparently healthy and active adults (age: 39.9 ± 12.2 years; VO2max: 47.4 ± 6.0 mL O2/kg∙min-1) participated in this study. Two types of submaximal estimations were performed to predict VO2max: one based on age-predicted maximal heart rate (HRmax) (ACSMsubmax,Fox), and the second using the actual HRmax measured during the exercise test (ACSMsubmax,measured). The measured VO2max was compared to these estimations obtained from a single exercise test. Both maximal and submaximal exercise tests significantly overestimated VO2max (ACSMmax: +9.8, p < 0.001; ACSMsubmax,Fox: +3.4, p < 0.001; ACSMsubmax,measured: +3.8 mL O2/kg∙min-1, p < 0.001). However, the submaximal estimations were closer to the measured VO2max (p < 0.001). This analysis demonstrated that the included methods overestimated the true VO2max. Nonetheless, the submaximal exercise tests provided a more accurate prediction of VO2max compared to the maximal exercise tests when using the ACSM running equation.

Effect of Short Bouts of Vigorous Stair Climbing on Cardiorespiratory Fitness in Women with Overweight and Obesity: A Pilot Feasibility Study.

We examined the effect of 4 weeks of a brief vigorous stair climbing exercise on cardiorespiratory fitness (CRF) and body composition in women with overweight or obesity. Twenty-six participants (age, 25.4±4.9 years; body mass index [BMI], 25.3±1.8 kg/m2) were randomly assigned to either a stair climbing exercise group (n=13) or a non-exercising control group (n=13). The stair climbing exercise group performed 20 sessions (supervised, five sessions/week over 4 weeks) of brief intermittent stair climbing exercise consisting of a 3-minute warm-up followed by three bouts of 20 seconds of stair climbing (≥80% of age-predicted maximum heart rate) interspersed with 2-minute recovery periods (total exercise duration=10 minutes/session). Peak oxygen uptake (VO2peak) was measured using a graded maximal treadmill test with the use of a standard open-circuit spirometry technique. Body composition was assessed with bioelectrical impedance analysis. All participants, except one who dropped out due to coronavirus disease 2019 (COVID-19) infection, completed the study with 100% attendance rates. There were significant interaction effects (group×time) on body weight, BMI, waist circumference, and CRF such that the stair climbing exercise group had significant (P≤0.01) reductions in body weight (66.5±4.6 to 65.2±4.6 kg), BMI (24.8±1.2 to 24.4±1.1 kg/m2), and waist circumference (78.0±3.7 to 76.5±4.1 cm) and improvements in VO2peak (31.6±2.5 to 34.9±2.6 mL/kg/min) compared with controls. Short bouts of vigorous stair climbing is a feasible and time-efficient exercise strategy for improving CRF in previously sedentary, young women with overweight and obesity.

Comparison of supine bicycle exercise versus treadmill exercise echocardiography in a cycling-naive population

Abstract Introduction Exercise echocardiography is a useful diagnostic test for the evaluation of coronary artery disease. Supine bicycle exercise echocardiography has the advantage of continuous monitoring of wall motion during exercise. On the contrary, the heart rate and workload is usually lower compared to treadmill exercise, especially between patients not used to cycling as is the case of many old adults. The aim of this study is to compare both exercise modalities. Methods A group of consecutive patients with chest pain underwent supine bicycle exercise echocardiography under a protocol adapted to the individual requirements. The operator chose between three protocols: light (5 watts every minute), medium (5 watts every 30 seconds) or intensive (10 watts every 30 seconds) according to age, sex and physical condition. The other group underwent treadmill exercise echocardiography using the Ball State University/Bruce Ramp protocol. Results A total of 902 patients were included. Of them, 258 patients underwent supine bicycle exercise echocardiography and 644 patients underwent treadmill exercise echocardiography. Mean age was 62.1 years (SD=13.4) and 48.5% of patients were women. Baseline characteristics were comparable in both groups, without significant differences regarding age, sex, body mass index, pre-test probability or image quality. There were no significant differences in the percentage of positive tests (5.0 vs. 5.3%, p = 0.883). However, the percentage of patients that achieved at least 85% of the predicted workload was significantly higher in the group of treadmill exercise echocardiography (91.3 vs. 45.0%, p &amp;lt; 0.001). The percentage of patients that achieved at least 85% of the age-predicted maximum heart rate was also significantly higher in the group of treadmill exercise echocardiography (76.7 vs. 44.2%, p &amp;lt; 0.001). Conclusions This study suggests that in a population not used to cycling, the use of supine bicycle exercise echocardiography, as opposed to the use of treadmill, hinders the achievement of an adequate maximum heart rate and workload, which can lead to inconclusive results. This should be considered while selecting the ischemic test to use.

Validation of the maximal cardiopulmonary exercise test in adolescents with major depressive disorder and comparison of cardiorespiratory fitness with sex- and age-related control values

Endurance training has been shown to be effective in treating adolescents with major depressive disorder (MDD). To integrate endurance training into the therapeutic setting and the adolescents' daily lives, the current performance status of the adolescents should be accurately assessed. This study aims to examine adolescents with MDD concerning exhaustion criteria during a cardiopulmonary exercise test (CPET), as well as to compare the values obtained thereon with sex- and age-related control values. The study included a retrospective examination of exhaustion criteria ((i) oxygen consumption (V̇O2) plateau, (ii) peak respiratory exchange ratio (RERpeak) > 1.0, (iii) peak heart rate (HRpeak) ≥ 95% of the age-predicted maximal HR, and (iv) peak blood lactate concentration (BLCpeak) > 8.0 mmol⋅L−1) during a graded CPET on a cycle ergometer in adolescents with MDD (n = 57). Subsequently, maximal V̇O2, peak minute ventilation, V̇O2 at the first ventilatory threshold, and peak work rate of participants who met at least two of four criteria were compared with published control values using an independent-sample t-test. Thirty-three percent of the total population achieved a V̇O2 plateau and 75% a RERpeak > 1.0. The HR and BLC criteria were met by 19% and 22%, respectively. T-test results revealed significant differences between adolescents with MDD and control values for all outcomes. Adolescents with MDD achieved between 56% and 83% of control values. Conclusions: The study shows that compared with control values, fewer adolescents with MDD achieve the exhaustion criteria on a CPET and adolescents with MDD have significantly lower cardiorespiratory fitness. Clinical trial registration: No. U1111-1145–1854.What is Known:• It is already known that endurance training has a positive effect on depressive symptoms.What is New:• A relevant proportion of adolescents with major depressive disorder do not achieve their V̇O2max during a graded cardiopulmonary exercise test.• Adolescents with major depressive disorder have significantly lower cardiorespiratory fitness compared to sex- and age-related control values.

A Novel Custom Cycle Ergometer Protocol to Determine V̇O2max: Validation with ACSM’s Cycle Ergometry Metabolic Equation

ABSTRACT Introduction Protocols for determination of maximal oxygen consumption (V̇O2max) on a cycle ergometer should be easily administered while maximizing physiological efficiency and minimizing premature local muscle fatigue for individuals of variable fitness levels. Current protocols typically increase workload by adding resistance to the flywheel; however, increasing pedal rate later in the test, rather than resistance, may provide increased physiological efficiency, yielding a more valid determination of V̇O2max. Purpose The purpose of this study was to design and validate a novel V̇O2max cycle ergometer protocol that can be used for measuring and predicting submaximal oxygen consumption (V̇O2) and V̇O2max during exercise testing in healthy, asymptomatic adults. Methods Subjects (n = 60, 19–60 yr old) performed a V̇O2max test using the new cycle ergometer protocol. Workload increases were based on predetermined incremental target heart rates (ITHR) using heart rate reserve. Stages commenced at a workload of 150 kg·m·min−1 (0.5 kg, 50 rpm) and increased every 2 min by adding 0.5 or 1.0 kg resistance based on ITHR. When an ITHR representing ≥60% heart rate reserve was achieved, workloads increased by 10 rpm for subsequent stages. Pearson’s r was used to examine relationships between predicted (American College of Sports Medicine cycle equation) and measured V̇O2 at workload intensities representing moderate, vigorous, and maximal exercise. Bland–Altman plots were used to display predicted and measured V̇O2 at all exercise intensities and heart rate values at maximal exercise. Results There was a strong and statistically significant correlation between predicted and measured V̇O2 at moderate (r = 0.92, P &lt; 0.001), vigorous (r = 0.94, P &lt; 0.001), and maximal (r = 0.90, P &lt; 0.001) exercise intensities. All subjects reached ≥90% of age-predicted maximum heart rate. Conclusion This novel cycle ergometer protocol was demonstrated to be a viable tool to predict and/or measure submaximal V̇O2 and V̇O2max in a population of healthy, asymptomatic adults.

Exercise Intolerance After Mild Traumatic Brain Injury Occurs in All Subtypes in the Adult Population.

Thematically grouped symptom clusters are present during the acute timeline of post-mild traumatic brain injuries (mTBI), representing clinical profiles called subtypes. Exercise intolerance has not been evaluated within the subtype classifications and, because guidelines support early submaximal aerobic exercise, further knowledge is required in regard to the exercise capabilities among the concussion subtypes. This cross-sectional study (n = 78) aimed to characterize the presence of exercise intolerance within the clinical subtypes and to explore performance on the Buffalo Concussion Treadmill Test (BCTT) in the adult subacute (2-12 weeks post-injury) mTBI population. All participants were evaluated using the BCTT to determine exercise tolerance. We first used the Neurobehavioral Symptom Inventory (NSI) questionnaire to assign each participant a primary subtype(s). To further explore all five subtypes (headache, cognitive, vestibular, ocular motor, and mood), participants were assessed using a multitude of thematically grouped assessments including self-reported questionnaires, clinical tests of vestibular and ocular motor function, balance function, and computerized cognitive testing. Thirty-seven (47%) subjects were exercise tolerant and 41 (53%) were exercise intolerant. There was no difference in the distribution of primary subtypes between the exercise tolerant and exercise intolerant groups. In addition, no significant differences were found between the exercise tolerant and exercise intolerant groups on other thematically grouped subtype assessments. The exercise intolerant group had a significantly higher resting heart rate (HR), lower percentage of age-predicted maximum HR achieved, lower Borg Rate of Perceived Exertion (RPE), and could walk on the treadmill for less time (lower duration) compared with the exercise tolerant group. The current findings suggest that exercise intolerance is common and pervasive across all five mTBI subtypes. A comprehensive mTBI assessment should include evaluation for exercise intolerance regardless of the primary clustering of symptoms and across patient populations. Therefore, early referral to physical therapists, athletic trainers, or medical clinics that can perform the BCTT may be helpful to initiate appropriate exercise prescriptions for patients with mTBI.

Applicability Of Existing Age-predicted Maximal Heart Rate Equations In Professional Youth Soccer Players.

Applicability Of Existing Age-predicted Maximal Heart Rate Equations In Professional Youth Soccer Players.

Are age-predicted equations valid in predicting maximum heart rate in individuals after stroke?

Purpose To investigate the validity of six age-predicted maximum heart rate (HRmax) equations after stroke. Material and methods Sixty individuals (54 (12) years; 64 (69) months after stroke) were included. A Cardiopulmonary Exercise Test (CPET) performed on a treadmill obtained the HRmax. The most used age-predicted equations were investigated: (1) 220-age, proposed by Fox; (2) 206.9– (0.67 × age), proposed by Gellish; (3) 208– (0.7 × age), proposed by Tanaka; (4) 216.6– (0.84 × age), proposed by Astrand; (5) 164– (0.72 × age) and (6) 200– (0.92 × age) proposed by Brawner. Results No statistically significant agreement was found between the HRmax obtained by the CPET and the one predicted by the equations 1–5 (–0.18 ≤ 95% confidence interval ≤0.79). A significant and moderate agreement was found between the HRmax obtained by the CPET and the one predicted by equation (6) (95% CI= 0.05–0.75; Intraclass Correlation Coefficient= 0.51). Bland-Altman plots showed that equations (1–4) and (6) overestimated the HRmax. Equation (6) presented the lower mean difference. Conclusions The equations developed for non-disabled individuals (1–4) are not adequate to be used in individuals after a stroke. Equation (6) (Brawner) showed the best results to be used in individuals after stroke; however, it should be used cautiously.

Workload and sex effects in comprehensive assessment of cutaneous microcirculation.

Workload and sex-related differences have been proposed as factors of importance when evaluating the microcirculation. Simultaneous assessments with diffuse reflectance spectroscopy (DRS) and laser Doppler flowmetry (LDF) enable a comprehensive evaluation of the microcirculation. The aim of the study was to compare the response between sexes in the microcirculatory parameters red blood cell (RBC) tissue fraction, RBC oxygen saturation, average vessel diameter, and speed-resolved perfusion during baseline, cycling, and recovery, respectively. In 24 healthy participants (aged 20 to 30years, 12 females), cutaneous microcirculation was assessed by LDF and DRS at baseline, during a workload generated by cycling at 75 to 80% of maximal age-predicted heart rate, and recovery, respectively. Females had significantly lower RBC tissue fraction and total perfusion in forearm skin microcirculation at all phases (baseline, workload, and recovery). All microvascular parameters increased significantly during cycling, most evident in RBC oxygen saturation (34% increase on average) and perfusion (9-fold increase in total perfusion). For perfusion, the highest speeds (>10mm/s) increased by a factor of 31, whereas the lowest speeds (<1mm/s) increased by a factor of 2. Compared to a resting state, all studied microcirculation measures increased during cycling. For perfusion, this was mainly due to increased speed, and only to a minor extent due to increased RBC tissue fraction. Skin microcirculatory differences between sexes were seen in RBC concentration and total perfusion.

The athlete's vein: venous adaptations in the lower limbs of endurance athletes.

Endurance exercise induces cardiovascular adaptations; the athletic phenotypes of the heart and arteries are well characterized, but few studies have investigated the effects of chronic exercise on the venous system. The aim of this study was to describe the anatomy and function of lower-limb deep and superficial veins in athletes compared with controls. Endurance-trained athletes and untrained controls (13 males, 7 females per group) were examined using ultrasound to measure vein diameter and flow, and air plethysmography to assess calf venous volume dynamics and muscle pump function at rest, during a single step, ambulation (10 steps) and after acute treadmill exercise (30 min ∼80% age-predicted heart rate maximum). Diameters of three of the seven deep veins assessed were larger in athletes (P ≤ 0.0167) and more medial calf perforators were detectable (5 vs. 3, P = 0.0039). Calf venous volume was 22% larger in athletes (P = 0.0057), and calf muscle pump ejection volume and ambulatory venous volume after 10 steps were both greater in athletes (20 and 46% respectively, P ≤ 0.0482). Following acute exercise, flow recovery profiles in deep and superficial veins draining the leg were not different between groups, despite athletes performing approximately four times more work. After exercise, venous volume and ejection volume were reduced by ∼20% in athletes with no change in controls (interaction, P ≤ 0.0372) and although ambulatory venous volume reduced, this remained greater in athletes. These findings highlight venous adaptations that compensate for the demands of regular endurance exercise, all of which are suited to enhance flow through the lower-limb venous system.NEW & NOTEWORTHY Although much literature exists describing adaptations to the heart and arteries in response to endurance exercise training, less is known about the effects on the venous system. Characteristics of "the athlete's vein" described here include deep and perforator vein remodeling, improved drainage, and greater calf venous volume at rest and on calf muscle pump activation. Following exercise, athletes demonstrated prompt flow recovery and appropriate volume reductions, and veins beneficially adapt to better tolerate the demands of regular physical activity.

The Buffalo Concussion Treadmill and Bike Tests in People With Mild-to-Moderate Traumatic Brain Injury: An Exploratory Clinical Audit.

To assess the performance on the Buffalo Concussion Treadmill and Bike Tests in nonathletic people following a mild-to-moderate traumatic brain injury. An outpatient rehabilitation clinic. Forty-nine patients with mild-to-moderate traumatic brain injury who underwent the Buffalo Concussion Treadmill or Bike Test as usual clinical care. A retrospective clinical audit. Demographics and brain injury-specific clinical data, Depression Anxiety Stress Scale; Rivermead Post-Concussion Symptom Questionnaire, and performance outcomes on the Buffalo Concussion Treadmill or Bike Test. Forty-nine patients (mean age: 33.7 ± 13.0 years), on average 56.2 ± 36.4 days post-injury, completed the Buffalo Concussion Treadmill or Bike Test. Fourteen patients stopped the test due to symptom exacerbation with a mean test duration of 8.1 ± 4.5 minutes, reaching an age-predicted maximum heart rate of 72.9% ± 12.4% and reporting a rating of perceived exertion of 13.4 ± 2.2. Those who terminated the test for other reasons had a significantly longer test duration (14.0 ± 4.7 minutes, P = .01), with a higher age-predicted maximum heart rate (83.3% ± 12.8%, P = .01) and rating of perceived exertion (17.0 ± 2.5, P = .01). Within the group who stopped for other reasons, 10 were due to symptoms deemed unrelated to the injury at the time of the test and 2 were stopped by the therapist for safety reasons. A significant but weak correlation between heart rate and rating of perceived exertion existed only for those who terminated the test for other reasons ( r = 0.38, P = .02). Overall, a shorter test duration was associated with higher scores of both self-reported depression ( r = -0.41, P < .01) and late postconcussion symptoms ( r = -0.40, P < .01). The Buffalo Concussion Treadmill or Bike Test can be used in the nonathletic mild-to-moderate traumatic brain injury population to differentiate between those who experience symptom exacerbation during exercise and those who do not based on symptom exacerbation, test duration, and poor perception of exertion. Further research is required to determine whether other reasons for test termination are related to the injury.

Heart Rate Responses at Rest, during Exercise and after Exercise Periods in Relation to Adiposity Levels among Young Nigerian Adults.

There is a dearth of comparative studies on heart rate (HR) abnormalities at rest, chronotropic responses during submaximal exercise, and such responses during recovery from submaximal exercise between healthy-weight and overweight/obese young adults. Eighty healthy young adults (30 men and 50 women) aged 19 to 33 years participated in the present study. A symptom-limited, submaximal, cycle ergometer exercise test of intensity targeted at 60% to 70% of the subject's age-predicted maximum HR was performed. The HR, blood pressure, and minute ventilation were measured at rest and during exercise. Post-exercise, HR was first measured at 1 minute of recovery and then every 2 minutes until the 5th minute. Our results showed significantly higher resting HR (P<0.001), lower percentage HR reserve during exercise (P<0.001), and slower HR recovery after exercise (P<0.05, P<0.01, or P<0.001) in overweight/obese men and women than in the non-overweight/obese controls. The prevalence of high resting HR, submaximal chronotropic incompetence, and blunted HR recovery were more common in the overweight/obese individuals than in the healthy-weight controls. Peak VO2 and ventilatory equivalent for oxygen were associated with resting HR, exercise HR parameters, and post-exercise HR recovery indices in both men and women. High resting HR, submaximal chronotropic incompetence, and blunted HR recovery in overweight/obese individuals in this study may be attributed to poor cardiorespiratory fitness and low respiratory efficiency.

Thermal strain is greater in the late afternoon than morning during exercise in the gym without airflow and air conditioning on a clear summer day.

There are no reports examining the time-of-day effect on team training sessions in the gym without airflow and air conditioning on thermal strain in the summer heat. We investigated this effect during badminton training sessions on a clear summer day. Nine male high school badminton players (Mean ± SD; age 17.1 ± 0.6 y, height 171 ± 4 cm, body mass 59 ± 7 kg) completed two 2.5-h badminton training sessions in the gym without airflow and air conditioning. The training sessions were started at 0900 h (AM) and 1600 h (PM) on separate days in August. Skin temperatures (chest, triceps, thigh, calf), infrared tympanic temperature, heart rate, thermal sensation and rating of perceived exertion were recorded at rest and at regular intervals during the sessions. Indoor and outdoor environmental heat stress progressively increased in AM and decreased in PM during the sessions. Ambient temperature (AM 30.1 ± 0.9°C; PM 33.2 ± 1.0°C: P < 0.001) and wet-bulb globe temperature (AM 28.1 ± 0.5°C; PM 30.0 ± 0.9°C: P = 0.001) during the sessions in the gym were higher in PM than AM. Mean skin temperature (AM 34.2 ± 1.0°C; PM 34.7 ± 0.7°C: P < 0.001), infrared tympanic temperature (AM 37.8 ± 0.5°C; PM 38.1 ± 0.4°C: P = 0.001) and thermal sensation (AM 2.7 ± 1.4; PM 3.3 ± 1.0: P < 0.001) during the sessions were higher in PM than AM. Body heat storage (AM 159 ± 30 W·m-2; PM 193 ± 30 W·m-2: P < 0.05) was greater in PM than AM. There were no time-of-day differences in the average heart rate (AM 75 ± 4% age-predicted maximal heart rate; PM 76 ± 5 age-predicted maximal heart rate: P = 0.534), body mass loss (AM 0.6 ± 0.3 kg; PM 0.8 ± 0.2°C: P = 0.079), the volume of water ingested (AM 1.5 ± 0.1 L; PM 1.6 ± 0.3 L: P = 0.447) and rating of perceived exertion (AM 16 ± 2; PM 16 ± 3: P = 0.281). This study indicates greater thermal strain in PM trial than in AM trial during team training sessions in the gym without airflow and air conditioning on a clear summer day. Therefore, athletes and coaches of indoor sports should perceive that athletes may be exposed to a greater risk for thermal strain in the late afternoon from 1600 h than in the morning from 0900 h during the sessions in the gym under these conditions.