Standardized Exercise Test Research Articles

Iron Deficiency Is Associated With Impaired Biventricular Reserve and Reduced Exercise Capacity in Patients With Unexplained Dyspnea

BackgroundIron deficiency (ID) is frequent and associated with diminished exercise capacity in heart failure (HF), but its contribution to unexplained dyspnea without a HF diagnosis at rest remains unclear. Methods and ResultsConsecutive patients with unexplained dyspnea and normal echocardiography and pulmonary function tests at rest underwent prospective standardized cardiopulmonary exercise testing with echocardiography in a tertiary care dyspnea clinic. ID was defined as ferritin of <300 µg/L and a transferrin saturation of <20% and its impact on peak oxygen uptake (peakVO2), biventricular response to exercise, and peripheral oxygen extraction was assessed. Of 272 patients who underwent cardiopulmonary exercise testing with echocardiography, 63 (23%) had ID. For a similar respiratory exchange ratio, patients with ID had lower peakVO2 (14.6 ± 7.6 mL/kg/minvs 17.8 ± 8.8 mL/kg/min; P = .009) and maximal workload (89 ± 50 watt vs 108 ± 56 watt P = .047), even after adjustment for the presence of anemia. At rest, patients with ID had a similar left ventricular and right ventricular (RV) contractile function. During exercise, patients with ID had lower cardiac output reserve (P < .05) and depressed RV function by tricuspid s' (P = .004), tricuspid annular plane systolic excursion (P = .034), and RV end-systolic pressure-area ratio (P = .038), with more RV–pulmonary artery uncoupling measured by tricuspid annular plane systolic excursion/systolic pulmonary arterial pressure ratio (P = .023). RV end-systolic pressure-area ratio change from rest to peak exercise, as a load-insensitive metric of RV contractility, was lower in patients with ID (2.09 ± 0.72 mm Hg/cm2 vs 2.58 ± 1.14 mm Hg/cm2; P < .001). ID was associated with impaired peripheral oxygen extraction (peakVO2/peak cardiac output; P = .036). Cardiopulmonary exercise testing with echocardiography resulted in a diagnosis of HF with preserved ejection fraction in 71 patients (26%) based on an exercise E/e' ratio of >14, with equal distribution in patients with (28.6%) or without ID (25.4%, P = .611). None of these findings were influenced in a sensitivity analysis adjusted for a final diagnosis of HFpEF as etiology for the unexplained dyspnea. ConclusionsIn patients with unexplained dyspnea without clear HF at rest, ID is common and associated with decreased exercise capacity, diminished biventricular contractile reserve, and decreased peripheral oxygen extraction.

Impacts of DigestaWell NRG Supplementation on Post Exercise Muscle Soreness in Unconditioned Horses, a Pilot Study

Exercising horses are commonly plagued by muscle fatigue and soreness, which can result in reduced performance ability. In the present study, ten unconditioned horses were fed 200g per day DigestaWell NRG, a commercial dietary supplement containing Yucca schidigera and Trigonella foenum-graecum, two herbs shown in other species to reduce post-exercise muscle pain and soreness. A control, unsupplemented group contained ten horses of similar age, breed, and gender. Horses completed a 50 minutes, ridden standardized exercise test of moderate intensity immediately prior to (Period1) and after 28 days of supplementation (Period2). Muscle soreness and tightness were evaluated 24 hours prior to and after each exercise test and used to determine the percent increase in post-exercise muscle soreness and tightness. Blood samples were collected before, and at 10 and 30 minutes, and 1, 4, and 24 hours post exercise. Plasma was analyzed for glucose, lactate, non-esterified fatty acid, tumor necrosis factor-α, and interleukin-1β concentrations. Data were analyzed by repeated measures ANOVA using SAS Enterprise Guide v. 7.1. No changes in plasma parameters were indicated between periods for unsupplemented horses (P > 0.1) during Period2, excepting glucose, which was greater during Period2 (P = 0.018). Supplemented horses had lesser concentrations of tumor necrosis factor-α (P = 0.016) and lactate (P = 0.058) during Period2 than during Period1. During Period2, supplemented horses experienced a smaller percent increase in post exercise muscle soreness (P = 0.031). DigestaWell NRG supplementation may benefit unconditioned horses undergoing moderate intensity exercise through reducing lactate production and inflammation.

The effect of time of feeding on plasma amino acids during exercise and recovery in horses.

Feeding management in horses suggests feeding horses in advance of exercise, particularly the grain portion of the diet. Plasma amino acids (AA) peak at 3 to 6 h postfeeding depending on the AA. The timeframe between feeding and exercise may affect the availability of AA during and after exercise. The purpose of this study was to observe the differences in plasma AA in horses fed prior to exercise or after exercise. Eight light type horses were fed a diet with adequate protein and AA for horses in light to moderate exercise. After an adjustment period, horses completed a standardized exercise test (SET). Relative to the SET, horses were fed either 2 h prior (PRE horses) to the SET, 1 h after completing the SET (POST horses), or horses remained fasted throughout the sampling period (FASTED horses). Plasma was drawn prior to exercise, at the peak of exercise as well as at 1, 2, 4, and 7 h postexercise. Plasma was analyzed for AA, glucose, lactate, creatinine, creatine kinase, ammonia, urea-N, and 3-methylhistdine. After completion of the SET and sampling period, horses entered a 1-wk recovery period, which was followed by another SET. The protocol repeated until horses rotated through all feeding protocols in the study (three SETs). The majority of the plasma AA were elevated in PRE horses compared with POST horses prior to the SET until 2 h postexercise where POST horses’ plasma AA concentrations became elevated and remained elevated until the end of the sampling period. In that same time frame, plasma AA for the PRE group decreased out to the end of the sampling period. The elevation of plasma AA in POST horses would be expected as they were fed at 1 h postexercise, whereas PRE horses were reaching a 4 h postfeeding time frame at this point. This elevation was not observed for plasma concentrations of isoleucine, leucine, methionine, and histidine. Concentrations of these AA initially were greater for POST horses in the postexercise period; however, they declined more rapidly than the other AA. The rapid decrease of some of the plasma AA concentrations may suggest uptake by muscle for recovery. This in conjunction with a decrease in plasma creatine kinase concentrations for POST horses suggests that feeding postexercise may facilitate better muscle protein balance (synthesis vs. breakdown) in the recovery period following exercise.

Improved Carotid Elasticity but Altered Central Hemodynamics and Carotid Structure in Young Athletes.

Young athletes most often exceed the physical activity recommendations of the World Health Organization. Therefore, they are of special interest for investigating cardiovascular adaptions to exercise. This study aimed to examine the arterial structure and function of young athletes 12–17 years old and compare these parameters to reference values of healthy cohorts. Carotid intima-media thickness (cIMT), carotid diameter, cIMT÷carotid diameter-ratio (cIDR), arterial compliance (AC), elastic modulus (Ep), β stiffness index (β), and carotid pulse wave velocity (PWVβ) were determined using ultrasound in 331 young athletes (77 girls; mean age, 14.6 ± 1.30 years). Central systolic blood pressure (cSBP) and aortic PWV (aPWV) were measured using the oscillometric device Mobil-O-Graph. Standard deviation scores (SDS) of all parameters were calculated according to German reference values. The 75th and 90th percentiles were defined as the threshold for elevated cIMT and arterial stiffness, respectively. Activity behavior was assessed with the MoMo physical activity questionnaire, and maximum power output with a standard cardiopulmonary exercise test. One-sample t-tests were performed to investigate the significant deviations in SDS values compared to the value “0”. All subjects participated in competitive sports for at least 6 h per week (565.6 ± 206.0 min/week). Of the 331 young athletes, 135 (40.2%) had cIMT >75th percentile, 71 (21.5%) had cSBP >90th percentile, and 94 (28.4%) had aPWV>90th percentile. We observed higher cIMT SDS (p < 0.001), cIDR SDS (p = 0.009), and AC SDS (p < 0.001) but lower β SDS (p < 0.001), Ep SDS (p < 0.001), and PWVβ SDS (p < 0.001) compared to the reference cohort. The cSBP SDS (p < 0.001) and aPWV SDS (p < 0.001) were elevated. In conclusion, cIMT and cIDR were higher in young athletes than in a reference cohort. Furthermore, young athletes presented better carotid elasticity and lower arterial stiffness of the carotid artery. However, central arterial stiffness was higher compared to the reference cohort. The thickening of the carotid intima-media complex in combination with a reduction in arterial stiffness indicates a physiological adaptation to exercise in youth.

Post-exercise pulsatility index indicates treatment effects in peripheral arterial occlusive disease (PAOD).

BackgroundHypothesis: Post-exercise measurements better discriminate PAOD-patients from healthy persons and they more sensitively detect hemodynamic improvements after treatment procedures than resting measurements.MethodsA total of 19 healthy volunteers and 23 consecutive PAOD-patients underwent measurements of peak systolic velocity (PSV), end-diastolic velocity (EDV), minimal diastolic velocity (MDV), time-averaged maximum velocities (TAMAX), resistance index (RI) and pulsatility index (PI) before and after a standard exercise test (at 1, 2, 3, 4 and 5 min) before and after treatment (incl. epidemiological data, PAOD risk factors and comorbidities).ResultsIn resting values, healthy persons and PAOD-patients did not differ significantly in any of the hemodynamic parameters. PSV increased after treatment in PAOD-patients by 5 cm/s (paired t‑test, p: 0.025); however, when the amplitude of autoregulatory changes related to the resting values were calculated, PAOD-patients showed clearly less hemodynamic changes after exercise than healthy persons (p: 0.04; 0.002; <0.001 for PSV, TAMAX and PI, resp.). The time course after exercise was compared by repeated measures of ANOVA. Healthy persons differed significantly in PI, RI and PSV from PAOD patients before and after treatment (p<0.001 each). The PAOD-patients revealed a significantly improved PI after treatment (p: 0.042). The only factor contributing significantly to PI independently from grouping was direct arterial vascularization as compared to discontinuous effects by an obstructed arterial tree.ConclusionHealthy persons cannot be well differentiated from PAOD-patients solely by hemodynamics at rest but by characteristic changes after standard exercise. Treatment effects are reflected by higher PI-values after exercise.

Altitude Cardiomyopathy Is Associated With Impaired Stress Electrocardiogram and Increased Circulating Inflammation Makers

Many sea-level residents suffer from acute mountain sickness (AMS) when first visiting altitudes above 4,000 m. Exercise tolerance also decreases as altitude increases. We observed exercise capacity at sea level and under a simulated hypobaric hypoxia condition (SHHC) to explore whether the response to exercise intensity represented by physiological variables could predict AMS development in young men. Eighty young men from a military academy underwent a standard treadmill exercise test (TET) and biochemical blood test at sea level, SHHC, and 4,000-m altitude, sequentially, between December 2015 and March 2016. Exercise-related variables and 12-lead electrocardiogram parameters were obtained. Exercise intensity and AMS development were investigated. After exposure to high altitude, the count of white blood cells, alkaline phosphatase and serum albumin were increased (P < 0.05). There were no significant differences in exercise time and metabolic equivalents (METs) between SHHC and high-altitude exposures (7.05 ± 1.02 vs. 7.22 ± 0.96 min, P = 0.235; 9.62 ± 1.11 vs. 9.38 ± 1.12, P = 0.126, respectively). However, these variables were relatively higher at sea level (8.03 ± 0.24 min, P < 0.01; 10.05 ± 0.31, P < 0.01, respectively). Thus, subjects displayed an equivalent exercise tolerance upon acute exposure to high altitude and to SHHC. The trends of cardiovascular hemodynamics during exercise under the three different conditions were similar. However, both systolic blood pressure and the rate–pressure product at every TET stage were higher at high altitude and under the SHHC than at sea level. After acute exposure to high altitude, 19 (23.8%) subjects developed AMS. Multivariate logistic regression analysis showed that METs under the SHHC {odds ratio (OR) 0.355 per unit increment [95% confidence intervals (CI) 0.159−0.793], P = 0.011}, diastolic blood pressure (DBP) at rest under SHHC [OR 0.893 per mmHg (95%CI 0.805−0.991), P = 0.030], and recovery DBP 3 min after exercise at sea level [OR 1.179 per mmHg (95%CI 1.043−1.333), P = 0.008] were independently associated with AMS. The predictive model had an area under the receiver operating characteristic curve of 0.886 (95%CI 0.803−0.969, P < 0.001). Thus, young men have similar exercise tolerance in acute exposure to high altitude and to SHHC. Moreover, AMS can be predicted with superior accuracy using characteristics easily obtainable with TET.

Preliminary analysis of the influence of breathing on heart rate variability in chronically ill patients with sleep apnea

Objective: Based on the hypothesis that respiration causes variability of circulatory indicators proposed by the holistic integrated physiology and medicine theory, the correlation between respiration and heart rate variability during sleep in chronically ill patients with abnormal sleep breathing is analyzed. Methods: Eleven chronically ill patients with abnormal sleep breathing and apnea-hypopnea index (AHI) ≥15 times/hr are recruited. After signing the informed consent, they completed the standardized symptomatic restrictive extreme exercise cardiopulmonary exercise testing (CPET) and sleep breathing monitoring Calculate and analyze the rules of respiratory nasal airflow and ECG RR interval heart rate variability during the oscillatory breathing (OB) phase and the normal steady breathing phase of the patient during sleep, and use the independent sample t test to compare with normal people and no sleep breathing abnormalities in the same period in this laboratory. Of patients with chronic diseases are more similar and different. Results: The peak oxygen uptake and anaerobic threshold (AT) of CPET in chronic patients with abnormal sleep apnea were (70.8±13.6)% Pred and (71.2±6.1)% Pred; 5 cases of CPET had exercise induced oscillatory breathing (EIOB), 6 An example is unstable breathing, which indicates that the overall functional status is lower than normal. In this group of patients with chronic diseases, AHI (28.8±10.0) beats/h, the ratio of the total time of abnormal sleep breathing to the total time of sleep (0.38±0.25); the length of the OB cycle (51.1±14.4)s. The ratio (Bn/HRV-B-n) of the number of breathing cycles in the normal and steady breathing period to the number of heart rate variability cycles in this group of patients with chronic diseases is 1.00±0.04, and the CV (SD of HRV-B-M/x) is (0.33 ±0.11), blood oxygen saturation (SpO2) did not decrease significantly, the average amplitude of heart rate variability (HRV-B-M) of each respiratory cycle rhythm was (2.64±1.59) bpm, although it was lower than normal people (P<0.05) , But it was similar to chronic patients without sleep apnea (P>0.05). In this group of patients with chronic diseases, the ratio of the number of respiratory cycles to the number of heart rate variability cycles (OB-Bn/OB-HRV-B-n) during OB is (1.22±0.18), and the average amplitude of heart rate variability for each respiratory cycle rhythm in OB (OB -HRV-B-M) is (3.56±1.57)bpm and its variability (OB-CV = SD of OB-HRV-B-M/x) is (0.59±0.28), the average amplitude of heart rate variability in each OB cycle rhythm (OB-HRV-OB-M) is (13.75±4.25)bpm, SpO2 decreases significantly during hypoventilation during OB, and the average decrease in SpO2 during OB (OB-SpO2-OB-M) is (4.79±1.39)%. The OB-Bn/OB-HRV-B-n ratio, OB-HRV-OB-M and OB-SpO2-OB-M in the OB period are all significantly higher than the corresponding indicators in the normal stable breathing period Large (P<0.01). Although OB-HRV-B-M has no statistically significant difference compared with HRV-B-M in normal stable breathing period (P>0.05), its variability OB-CV is significantly increased (P<0.01). Conclusion: The heart rate variability of chronic patients with abnormal sleep breathing in the OB phase is greater than that of the normal stable breathing period. When the breathing pattern changes, the heart rate variability also changes significantly. The number of breathing cycles in the stable breathing period is equal to the number of heart rate variability cycles.The ratio is the same as that of normal people and chronically ill patients without sleep apnea, confirming that heart rate variability is respiratory origin; and the reduction of heart rate variability relative to the respiratory cycle during OB is directly caused by hypopnea or apnea at this time, and heart rate variability is also breathing source.

Safety of Exercise Testing in the Clinical Chinese Population.

This 18-year cross-sectional study was conducted to provide data on the safety of exercise testing in the clinical Chinese population. We retrospectively identified exercise tests completed at Xiangya Hospital of Central South University from January 1, 2002 to December 31, 2019. From 43,130 unique individuals (50.9% female), a total of consecutive 50,142 tests (standard exercise testing 29,466; cardiopulmonary exercise testing 20,696) were retrieved. Demographics, patients' medical history, exercise testing characteristics, and exercise testing-related adverse events were described. Safety data is expressed as the number of adverse events per 10,000 tests, with 95% confidence interval. The average patients' age was 51 ± 13 years. The majority of patients were diagnosed with at least one disease (N = 44,941, 89.6%). Tests were maximal or symptom-limited. Common clinical symptoms included dizziness (6,822, 13.6%), chest pain or distress (2,760, 5.5%), and musculoskeletal limitations (2,507, 5.0%). Out of 50,142 tests, three adverse events occurred, including one sustained ventricular tachycardia, one sinus arrest with junctional escape rhythm at a rate of 28 bpm, and one syncopal event with fecal and urinary incontinence. The rate of adverse events was 0.8 events per 10,000 tests (95% confidence interval, 0.2–3.0) in men, 0.4 per 10,000 tests (0.7–2.2) in women, and 0.6 per 10,000 tests (0.21.8) total. This study represents the largest dataset analysis of exercise testing in the clinical Chinese population. Our results demonstrate that clinical exercise testing is safe, and the low rate of adverse events related to exercise testing might be due to the overall changes in clinical practice over time.

Why are the tarahumara amerindians in mexico such powerful mountain runners?

The Tarahumara Amerindians in Mexico are extremely potent runners on long mountain trails. We have analyzed publications to find causes. Traditionally the Tarahumara live alternating at altitudes between 2400 m and 800 m. Distances from homes to fields and village centers are large and covered on foot since childhood. Men and women take part in running competitions often with kickballs. Investigated runs lasted on average 8:42 h (78 km without ascent) and 6:58 h (63km), respectively. The intensity during the short race amounted to 70% of estimated V˙O2max (ranging between 41 and 70 ml/(kg*min)), energy expenditure reached 21000 kJ. People run barefoot or with thin sandals resulting in increased forefoot impact and storage of elastic energy. This and the slim frame with little subcutaneous fat reduce energy consumption. The vegetarian nutrition contains many carbohydrates and plant proteins, little fat and cholesterol. Hemoglobin concentration tends to increased values. Noncoding beta-chain variants possess no importance for oxygen affinity. The hearts are not enlarged like in endurance athletes. Genes show little European admixture. Gene enrichment in musclerelated pathways suggests a contribution to physical resistance. Conclusions: Explanations for the extreme endurance are favorable biomechanical conditions and physical training beginning during childhood. Running on slopes and changing living sites between 800 and 2400 m play an additional role. Standard exercise tests and genetic investigations are necessary in future. Key Words: Altitude, Hypoxia, Long Distance Running, Genetics

Influence of indirect factors and its effect analysis on performance level of Slovak warmblood horse breed

Article Details: Received: 2020-10-21 | Accepted: 2020-11-27 | Available online: 2021-01-31 https://doi.org/10.15414/afz.2021.24.mi-prap.105-108 During their career, horses are affected by a large number of direct and indirect factors. The aim of our study was to determine the effect of indirect factors, such as year of start, sex, breed, number of starts, age and proportion of genes of Slovak Warmblood horse breed. For determination of indirect factors on performance level, results from test efficiency and final placement in showjumping category 4, 5 and 6 years old young horses were used. 540 horses of Slovak Warmblood breed were analysed between 2015 - 2019 and 1155 data samples were collected. Based on the results of the linear model, parameters – the effect of gender and the influence of the gene proportion of Slovak Warmblood horse had statistically significant influence (p&lt;0.05). High significant effect (p&lt;0.001) on performance of Slovak Warmblood horse was observed in parameters – year of start, age during start and breed. Keywords: horse, indirect factors, performance References CASTEJON-RIBER, C. et al. (2017). Objectives, Principles and Methods of Strength Training for Horses. Journal of Equine Veterinary Science , 56, 93-103. http://dx.doi.org/10.1016/j.jevs.2017.04.011 De MARÉ, L. et al. (2017). Standardized exercise tests in horses: current situation and future perspectives. Vlaams Diergeneeskundig Tijdschrift , 86(2): 63-72. http://dx.doi.org/10.21825/vdt.v86i2.16290 GOŠČÍK, Z. (1993). Fyziologický základ tréningu koňa atléta. Nitra: Mgr. Marta Ölvecká. ISBN 80-900413-6-1, 70p. GOŠČÍK, Z. (2000). Racionálny tréning športových koní a jeho vplyv na ich dlhodobé využitie. [online]: http://www.horses.sk/'konfer/kratr. htm HENNESSY, K. et al. (2008). Vendor and purchaser expectations: differential market segment requirements for sport horses. In proceeding from 4th International Conference of International Society for Equitation Science . Dublin (p. 53). KEARSLEY, C. G. S. et al. (2008). Use of competition data for genetic evaluations of eventing horses in Britain: analysis of the dressage, showjumping and cross country phases of eventing competition. Livestock Science , 118(1), 72-81. https://doi.org/10.1016/j.livsci.2008.01.009 KOENEN, E. (2002). Genetic evaluations for competition traits of warmblood sport horses. In WBFSH seminar , Budapest. KOENEN, E. P. C., ALDRIDGE, L. I. &amp; PHILIPSSON, J. (2004). An overview of breeding objectives for warmblood sport horses. Livestock Production Science , 88(1), 77-84. http://dx.doi.org/10.1016/j.livprodsci.2003.10.011 KRATTENMACHER, N. et al. (2014). The role of maternal lineages in horse breeding: Effects on conformation and performance traits. In proceeding from 10th World Congress on Genetics Applied to Livestock Production , Vancouver, Canada (p. 17-22). LUEHRS-BEHNKE, H. et al. (2002). Genetic associations among traits of the new integrated breeding evaluation method used for selection of German warmblood horses. Veterinarija ir zootechnika , 18(40), 90-93. RICARD, A.; BRUNS, E.; CUNNINGHAM, E. P. (2000). Genetics of performance traits. The genetics of the horse , (p. 411-538). http://dx.doi.org/ 10.1079/9780851994291.0000 RICARD, A. &amp; BLOUIN, C. (2011). Genetic analysis of the longevity of French sport horses in jumping competition. Journal of Animal Science , 89(10), 2988-2994. http://dx.doi.org/10.2527/jas.2011-3931 STEWART, I. D., WOOLLIAMS, J. A. &amp; BROTHERSTONE, S. (2010). Genetic evaluation of horses for performance in dressage competitions in Great Britain. Livestock Science , 128(1), 36-45. http://dx.doi.org/10.1016/j.livsci.2009.10.011 STEWART, M. et al. (2011). Assessment of positive emotions in horses: Implications for welfare and performance. Journal of Veterinary Behavior: Clinical Applications and Research , 6(5), 296. http://dx.doi.org/10.1016/j.jveb.2011.05.014 SCHUBERTOVÁ, Z., PAVLÍK, I. &amp; CANDRÁK, J. (2014). The influence of the genomic data on the showjumping horses performance evaluation. Journal of Central European Agriculture , 15(2), 33-40. http://dx.doi.org/10.5513/JCEA01/15.2.1447 SCHRÖDER, W. et al. (2012). A genome‐wide association study for quantitative trait loci of show‐jumping in Hanoverian warmblood horses. Animal genetics , 43(4), 392-400. http://dx.doi.org/10.1111/j.1365-2052.2011.02265.x Van VELDHUIZEN, A. E. (1997). Breeding value estimation for riding horses in the Netherlands. In 48th Ann. Meet. EAAP , Vienna, Austria

A Standardized Buffalo Concussion Treadmill Test Following Sport-Related Concussion in Youth: Do ActiGraph Algorithms Matter?

Current recovery guidelines following sport-related concussion (SRC) include 24-48 hours of rest followed by gradual return-to-activity with heart rate (HR) maintained below symptom threshold. Additionally, the monitoring of physical activity (PA) post-SRC using ActiGraph accelerometers can provide further objective insight on amounts of activity associated with recovery trajectories. Cut-point algorithms for these devices allow minute-by-minute PA to be classified into intensity domains; however, studies have shown different algorithms employed on the same healthy participant dataset can produce varying classifications. To identify the most physiologically appropriate cut-point algorithm (Evenson or Romanzini) to analyze ActiGraph data in concussed youth with comparisons to HR response on the Buffalo Concussion Treadmill Test (BCTT). Prospective cohort study. Sport-concussion clinic within a university setting. Eleven high-school students (5 male, 6 female; median [range] age =16 years [15-17], height = 177.8 cm [157.5-198.1], weight = 67 kg [52-98], body mass index = 22 kg/m2 [17-31]) involved in high-risk sport who sustained a physician diagnosed SRC. Evenson and Romanzini algorithm PA intensity domains via ActiGraph data and HR during the BCTT. There were differences in moderate (P = .001) and vigorous (P = .002) intensities between algorithms, but no difference in light (P = .548). Evenson classified most of the time as moderate intensity (57.03% [0.00-94.12%]), whereas Romanzini classified virtually all PA as vigorous (88.25% [2.94-97.06%]). PA based on HR (stages 1-7: 20-39% HR reserve (HRR), stages 8-13: 40-59% HRR, stages 14 and above: 60-85% HRR) indicated the BCTT primarily involves light-to-moderate intensity, and therefore is better represented by the Evenson algorithm. The Evenson algorithm better characterizes the HR response during a standardized exercise test in concussed individuals and therefore should be used to analyze ActiGraph PA data in a concussed paediatric population.

Post‐exercise endoscopic and cytologic diagnosis of equine asthma syndrome in asymptomatic Brazilian pacers

SummaryThe objectives were: 1. to investigate the occurrence of equine asthma syndrome (EAS) in a group of Campolina and Mangalarga Marchador horses through post‐exercise respiratory endoscopy and cytology; 2. compare the efficiency of different diagnostic criteria; and 3. compare the incidence of EAS by breed, age group and sex. A standardised exercise test was conducted in the field, followed by respiratory endoscopy and bronchoalveolar lavage and fluid collection 30 min post‐exercise. Clinical evaluation pre‐ and post‐exercise, respiratory endoscopy post‐exercise and bronchoalveolar lavage, also post‐exercise, were conducted in 30 horses (15 Campolina and 15 Mangalarga Marchador) aged 3–18 years, without a history of respiratory illness and without clinical evidence of active respiratory disease. All horses were in active training and were considered fit to participate in equestrian competition characteristic of these breeds. Post‐collection, the horses were subdivided into healthy or EAS‐positive, depending on several diagnostic criteria. Statistical comparisons between breeds, age brackets (up to 7 years of age and above 7 years of age) and sex were conducted using appropriate statistical tests. According to bronchoalveolar lavage fluid (BALF) cytology, 56.7% of the horses showed at least one inclusion criteria that contributed to classification as EAS‐positive. Of those, only one was classified as moderate EAS, while the others were classified as mild. Total cell count in the BALF above 530 cells/µL was the single most common diagnostic criteria (100%), followed by increased tracheal mucus (53%) at endoscopy, eosinophilia (47%) and neutrophilia (35%) in BALF. Significant differences were found between macrophage and lymphocyte numbers according to breed, but no other differences between breeds, age brackets, sex or status (healthy vs. EAS‐positive). A high occurrence of EAS was found in competition‐ready Mangalarga and Campolina pacer horses in this study.

Heart rate kinetics during standard cardiopulmonary exercise testing in heart transplant recipients: a longitudinal study.

AimsHeart transplantation (HTx) results in complete autonomic denervation of the donor heart, causing resting tachycardia and abnormal heart rate (HR) responses to exercise. We determined the time course of suggestive cardiac reinnervation post HTx and investigated its clinical significance.Methods and resultsHeart rate kinetics during standard cardiopulmonary exercise testing at 2.5–5 years after HTx was assessed in 58 patients. According to their HR increase 30 s after exercise onset, HTx recipients were classified as denervated (slow responders: <5 beats per minute [b.p.m.]) or potentially reinnervated (fast responders: ≥5 b.p.m.). Additionally, in 30 patients, longitudinal changes of maximal oxygen consumption and HR kinetics were assessed during the first 15 post‐operative years. At 2.5–5 years post HTx, 38% of our study population was potentially reinnervated. Fast responders were significantly younger (41 ± 15 years) than slow responders (53 ± 13 years, P = 0.003) but did not differ with regard to donor age, immunosuppressive regime, cardiovascular risk factors, endomyocardial biopsy, or vasculopathy parameters. While HR reserve (56 ± 20 vs. 39 ± 15 b.p.m., P = 0.002) and HR recovery after 60 s (15 ± 11 vs. 5 ± 6 b.p.m., P < 0.001) were greater in fast responders, resting HR, peak HR of predicted, and peak oxygen consumption of predicted were comparable.ConclusionsSigns of reinnervation occurred mainly in younger patients. Maximal oxygen consumption was independent of HR kinetics.

Abstract 14479: Fontan Patients With Dominant Left Ventricular Morphology Have Severe Ventricular Electromechanical Discoordination Associated With Worse Exercise Capacity

Introduction: Fontan patients with a single left ventricle (SLV) develop late systolic and diastolic dysfunction. The development of SLV dysfunction has been associated with abnormal loading conditions, myocardial ischemia and fibrosis, and compromised ventricular-aortic coupling. However, electromechanical discoordination, a prime determinant of ventricular performance, has not been adequately evaluated in patients with SLV. Hypothesis: Patients with SLV and Fontan circulation will have abnormal electromechanical discoordination compared to controls, and this will be associated with their functional status. Methods: Patients with SLV (n=20) and healthy controls (n=20) underwent MRI-based tissue deformation analysis. Circumferential strain and strain rate data were used to calculate systolic stretch fraction (SSF) and diastolic relaxation fraction (DRF) (Figure 1). SSF is the proportion of myocardial segments undergoing relaxation in systole, while the DRF is the proportion of myocardial segments undergoing contraction in diastole. SSF and DRF were correlated with standard MRI indices and standard exercise tests. Results: Global circumferential strain was decreased in SLV compared to controls (16.4±2.7 vs 19.9±1.7, P&lt;0.001). SLV had increased median SSF when compared to the LV of controls [(0.023 (IQR: 0.006-0.036) vs. 0.007 (IQR: 0.006-0.013), P=0.023] and increased median DRF [0.39 (IQR: 0.30-0.44) vs. 0.30 (IQR: 0.26-0.32), P=0.002]. SSF correlated with the peak VO 2 index (R=-0.56, P=0.027) and DRF correlated with ejection fraction (R=-0.56, P=0.010). Conclusion: Fontan patients with SLV exhibit systolic and diastolic electromechanical discoordination, which is associated with lower peak VO 2 and reduced ejection fraction, respectively. Electromechanical discoordination might contribute to global SLV dysfunction by limiting both effective contractility and preload generation.

Measurement of Endurance of Untrained Five-Year-Old and Six-Year-Old Horses Raised in Multi-age Herds on Pasture

The objective of this study was to explore how the endurance of five-year-old horses, kept out on pasture all their life and ridden for the first time well into their fifth year of age, developed within one year and compared to that of six-year-old horses raised under the same conditions and to other horses. Horses were submitted to a standardized exercise test (SET) to calculate their v4 (velocity run under defined conditions inducing 4 mmol/L of blood lactate concentration (LA)) and v180 (velocity run under defined conditions inducing a heart rate of 180 beats/min). The test consisted of up to five consecutive intervals at increasing speed until the blood LA of a horse increased above 4 mmol/L. The blood LA measured after each interval was plotted exponentially against running speed to derive v4 from the blood lactate–running speed relationship, and the mean heart rate during the intervals was plotted linearly against running speed to derive v180 from the heart rate–running speed relationship. The following were examined: (1) the development of v4 and v180 of five-year-old horses within one year through measurements in September and in the following July and September; the comparison of endurance variables (2) between five-year-olds and six-year-olds; (3) between six-year-olds on consecutive years; and 4) between six-year-olds and foreign horses. The results showed that: (1) there were no changes of either variable within one year (repeated measures ANOVA P > .05); (2) there were no significant differences between five-year-olds and six-year-olds (one-way ANOVA P > .05); (3) no significant differences between six-year-old groups (one-way ANOVA; P > 05); and (4) foreign horses had higher v4 and v180 values than six-year-olds (one-way ANOVA; P = .0001 and P = .003, respectively). There was no significant relationship between v4 and v180 (P > .05; r2 = 0.02). In conclusion, one additional year on pasture in multiage herds did not increase the endurance variables of five-year-old horses. Thus, the endurance appeared to be consolidated in these horses at the age of five years, and additional training seems to be necessary to increase it.

Prevalence of exercise-induced bronchoconstriction and laryngeal obstruction in adolescent athletes.

ObjectivesTo study the prevalence of exercise‐induced bronchoconstriction (EIB) and exercise‐induced laryngeal obstruction (EILO) in adolescent athletes.MethodsAll adolescents (n = 549) attending first year at a sports high school in 2016 and 2017, were invited to answer a questionnaire on respiratory symptoms. The 367 responding participants were divided into two groups based on whether they reported exercise‐induced dyspnea (dyspnea group) or not (nondyspnea group). Randomly selected participants in each group were invited to undergo two standardized exercise tests, an EIB test and a continuous laryngoscopy exercise (CLE) test, to investigate EILO.ResultsIn total, 98 participants completed an EIB test, 75 of whom also completed a CLE test. Positive EIB tests: eight of 41 in the dyspnea group and 16 of 57 in the nondyspnea group. Positive CLE tests: 5 of 34 in the dyspnea group and three of 41 in the nondyspnea group. The estimated prevalence of EIB was 23.1% (95% confidence interval [CI]: 14.5–33.8) and of EILO 8.1% (95% CI: 2.5–18.5) in the whole study population. No differences in prevalence of EIB or EILO were found between the dyspnea and the nondyspnea groups.ConclusionEIB was highly prevalent in this cohort of adolescent athletes. EILO was less prevalent, but represents an important differential diagnosis to EIB. Self‐reported exercise‐induced dyspnea is a weak indicator for both EIB and EILO and standardized testing should be provided.

Which functional outcome measures can we use as a surrogate for exercise capacity during remote cardiopulmonary rehabilitation assessments? A rapid narrative review.

IntroductionThe coronavirus disease 2019 (COVID-19) pandemic has seen many cardiopulmonary rehabilitation services delivering programmes remotely. One area of concern is how to assess exercise capacity when a supervised exercise test is not possible. The aim of this review was to examine the relationship between functional exercise tests and recommended exercise tests for cardiopulmonary rehabilitation.MethodsA rapid narrative review was carried out. Searches were conducted by two of the study authors. The study had the following features. Participants: adults, all with long-term conditions; intervention: any/none; outcome: Duke activity status index (DASI), sit to stand (STS, 30 s, 1 min and 5 repetitions), short physical performance battery (SPPB), 4-metre gait speed (4MGS) or step test (Chester/others) AND directly compared to one of the recommended exercise tests for cardiopulmonary rehabilitation: 6-min walk test (6MWT), incremental shuttle walk test (ISWT) or cardiopulmonary exercise test (CPET) in terms of reporting agreement/correlation; Study design: primary research only, controlled trials or observational studies.ResultsSixteen articles out of 249 screened were included (n=2271 patients). Overall, there were weak–strong correlations for the included tests with a recommended exercise test (r=0.38–0.85). There were few reported issues with feasibility or safety of the tests. However, all tests were supervised in a clinical setting. The test that had the highest correlation with the field walking test was the 4MGS with the ISWT (r=0.78) and with the 6MWT (r=0.85).DiscussionThe 4MGS has the highest correlation with routine measures of exercise tolerance. However, it may be difficult to standardise in a remote assessment or to prescribe exercise from. Clinicians should strive for face-to-face standardised exercise tests where possible to be able to guide exercise prescription.

Venous Blood Acid-Base Status in Show Jumper Horses Subjected to Different Physical Exercises

The aim of this study was to assess whether acid-base profile exhibits changes in regularly trained show jumping horses undergoing increasing exercise workloads. Seven female Italian saddle horses were subjected to three different physical exercise trials of increasing workload identified as three exercise phases (EPs). During EPI horses were subjected to a standardized exercise test consisting of 15 minutes of treadmill, during EPII horses were subjected to a show jumping test (height, 0.9–1.1 m; course length, 300 m), during EPIII horses underwent two jumping sessions carried out over two consecutive days. Blood samples were collected at rest (TPRE), after exercise (TPOST), and 30 minutes after the end of exercise (TPOST30). The values of pH, partial pressure of carbon dioxide (Pco2), partial pressure of oxygen (Po2), bicarbonate level (HCO3−), hemoglobin (Hb), and hematocrit (Hct) were measured. A significant effect of exercise workload and time (P < .001) on Po2, Pco2, HCO3−, Hb, and Hct values was found. The variation in the studied parameters resulted mostly reversible within TPOST30 in horses when subjected to EPI and EPII, whereas Po2, Hb, and Hct remained higher at TPOST30 than TPRE in horses when subjected to the second day of jumping section (EPIII) indicating a failure to recover. The results suggest that jumping sessions carried out over two consecutive days represent extra workload for horses, and this should be taken into account by veterinarian to prevent acid-base imbalance and for the maintenance of health and performance in equine athletes.

Evaluation of Aerobic Exercise Intensity in Patients with Coronary Artery Disease and Type 2 Diabetes Mellitus.

(1) Background: Physical activity is recommended in patients with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD) to reduce hyperglycemia and cardiovascular risk. Effective aerobic exercise intensity, however, is not well defined. (2) Methods: 60 consecutive patients performed cardiopulmonary exercise testing (CPX) of 30 min duration targeting a respiratory exchange ratio (RER) between 0.85 and 0.95, being strictly aerobic. Plasma glucose (PG) was measured before and after CPX as well as one and two h after exercise. Maximum exercise intensity was evaluated using a standard bicycle exercise test. (3) Results: 50 patients completed the protocol (62 ± 10 years, BMI (body mass index) 30.5 ± 4.9 kg/m2, HbA1c (glycated haemoglobin) 6.9 ± 0.8%, left ventricular ejection fraction 55 ± 8%). Aerobic exercise capacity averaged at 32 ± 21 Watt (range 4–76 Watt) representing 29.8% of the maximum exercise intensity reached. PG before and after CPX was 9.3 ± 2.2 and 7.6 ± 1.7 mmol/L, respectively (p < 0.0001). PG was further decreased significantly at one and two h after exercise to 7.5 ± 1.6 mmol/L and 6.0 ± 1.0 mmol/L, respectively (p < 0.0001 for both as compared to PG before CPX). (4) Conclusions: Aerobic exercise capacity is very low in patients with CAD and T2DM. Exercise at aerobic intensity allowed for significant reduction of plasma glucose. Individual and effective aerobic exercise prescription is possible by CPX.

Physical effort of middle-aged women in a university hospital – Field tests in comparison to standardized cardiopulmonary exercise testing (CPET)

Physical effort of workload of female employees in the healthcare system is perceived to rise. Research focused mainly on physical activity levels of registered nurses (RN). Therefore, we investigated physical strain during daily routine of other hospital workers next to RN. O2uptake, heart rate, breathing frequency and ventilation were measured in 33 female medical (associate) professionals (MAP) and Cleaners&Helpers (Cl&H) using Oxycon Mobile. Physical work load was compared to standardized CPET. Wilcoxon-test and ANOVA were calculated using SPSS 20.0. Cl&H performed heavy-lifting and had the lowest power during CPET. The O2-uptake for heavy-lifting as strong effort, differed significantly from office work (p < 0.001) and bedside-patient-care (p = 0.001). Compared with metabolic equivalent (MET) cleaning, heavy-lifting, and office work are underestimated. Bedside-patient-care, walking, pushing performed by MAP are overestimated. While Cl&H had the lowest maximal power in CPET, their work required the highest O2-uptake. The tasks are underestimated in the MET-tables.