Feasibility of the A-STEP for the assessment of exercise capacity in people with cystic fibrosis.

OBJECTIVES: To evaluate feasibility of the Alfred Step Test Exercise Protocol (A-STEP) for the assessment of exercise capacity in adults and children with cystic fibrosis (CF); in adults to test whether demographics and/or lung function correlated with exercise capacity. METHODS: Adults and children with stable CF from two centres completed the A-STEP (a recently developed incremental maximal-effort step test). Feasibility was evaluated by: usefulness for exercise capacity assessment (measures of exercise capacity were: level reached, exercise-induced desaturation, and achievement of at least one maximal effort criteria); safety; operational factors; time to complete; floor and/or ceiling effects. We used multiple linear regression to test whether demographics and/or lung function correlated with exercise capacity. RESULTS: A total of 49 participants: 38 adults (18 male), percent predicted (pp) forced expiration in one second (FEV1 ) 29-109, aged 22-48 years and 11 children (6 male), ppFEV1 68-107, aged 10-15 years were included. Levels reached (mean (SD) [range]) were 10.2 (2.4) [6-15] (adults), 10.1 (2.5) [7-14] (children); desaturation (change between baseline and peak-exercise SpO2 ): was 8.4 (3.8 [0-15]% (adults), 2.0 (2.0) [0-7]% (children). A total of 8 (21%) adults and no children desaturated <90% SpO2 . At least one criterion for maximal effort was reached by 33 (84%) adults and 10 (91%) children. There were no adverse events. The A-STEP was straightforward to use and carried out by one operator. A total of 26 (68.4%) adults and 7 (63.6%) children completed the test within the recommended 8-12 min. All participants completed a minimum of 6 levels, and completed the test before the final 16th level. In adults, ppFEV1 and ppFVC correlated with the level reached (r = 0.55; p = <0.001 and r = 0.66, p = <0.0001) and desaturation (r = 0.55, p = <0.001 and r = 0.45, p = <0.005). CONCLUSION: In adults and children with stable CF, the A-STEP was feasible, safe, and operationally easy to use for the assessment of exercise capacity, without floor or ceiling effects. In adults, lung function correlated with exercise capacity.

A Model-free Approach for Testing Association.

The question of association between outcome and feature is generally framed in the context of a model based on functional and distributional forms. Our motivating application is that of identifying serum biomarkers of angiogenesis, energy metabolism, apoptosis, and inflammation, predictive of recurrence after lung resection in node-negative non-small cell lung cancer patients with tumor stage T2a or less. We propose an omnibus approach for testing association that is free of assumptions on functional forms and distributions and can be used as a general method. This proposed maximal permutation test is based on the idea of thresholding, is readily implementable and is computationally efficient. We demonstrate that the proposed omnibus tests maintain their levels and have strong power for detecting linear, nonlinear and quantile-based associations, even with outlier-prone and heavy-tailed error distributions and under nonparametric setting. We additionally illustrate the use of this approach in model-free feature screening and further examine the level and power of these tests for binary outcome. We compare the performance of the proposed omnibus tests with comparator methods in our motivating application to identify preoperative serum biomarkers associated with non-small cell lung cancer recurrence in early stage patients.

Development of the A-STEP: A new incremental maximal exercise capacity step test in cystic fibrosis.

BACKGROUND: Exercise testing is important in people with cystic fibrosis (pwCF). The aim was to develop an incremental maximal step test to assess exercise capacity across the range of pwCF, without floor or ceiling effects, within restrictions of space, and infection prevention. METHODS: The step test was developed in adults with stable CF. Subjects assisted in selecting: step height, start rate, increments, stage and test duration parameters. Equipment to externally pace and time the test and measure exercise parameters were selected. Reasons for stopping, criteria for achieving a maximal test, and key outcome measures were determined. Documentation to record and standardize the test and instructions to set up the metronome and timer App were developed. Infection control practices were considered. RESULTS: Eight subjects were recruited to develop the Alfred Step Test Exercise Protocol (A-STEP) on a 20 cm portable step. The A-STEP package included a pretest information sheet, clinical assessment and instructions, recording worksheet, and the metronome/timer instructions. The test started at 18 steps/min. Each level increased by two steps/min to a maximum of 48 steps (Level 16). Results were presented as mean (SD) [range] for: age 30.63 (5.89) [21-39] years; FEV1 58.13 (18.33) [32-89]%; levels: 10.31 (3.29) [6-15.5]. The A-STEP required space of 2 m2 and complied with current infection control guidelines. CONCLUSIONS: The A-STEP is a new incremental maximal step test to assess exercise capacity in pwCF, without floor or ceiling effects. It addresses the issues of space restrictions and the need for strict infection prevention in the clinical setting.

The ST segment depression pattern in asymptomatic peri-menopausal female athletes.

BACKGROUND: ST segment has not been well investigated in asymptomatic peri-menopausal female athletes, when the CV risk is higher. AIMS: The aims of the study is to investigate the prevalence of ST segment depression in peri-menopausal female athletes, divided in four age groups. METHODS: in a cohort of 6010 female athletes aged 45-65 years old, 161 subjects were selected for the presence of ST segment depression, revealed by maximal ergometric test. All athletes were also evaluated by physical examination and echocardiography. Inclusion criteria for ST segment depression were ST depression >0.5 mm respect to baseline and its depth was divided in 0.5 mm, 0.5-1 mm, 1-2 mm categories. Its behavior was classified in ascending, horizontal and descending and it was studied in relation to the age range (<51; 51-55; 56-60; >60). RESULTS: ST segment depression was mainly evident in inferolateral leads in all groups (63%, 70,3%, 71%, 63,6%, for <51; 51-55, 56-60 and 61-65 respectively) with horizontal pattern (52,2%, 59,5%, 57,8%, 63,6%) and 1-2 mm depth (43,5%, 46,7%, 60,6%), with the exception of the range 51-55, mainly showing a depth of 0,5-1 mm (45,9%). The older group showed increased SBP (137.5 mmHg, p = 0.007) and BMI (24.3, p = 0.093) values. Mitral prolapse was shown in 11,8% while 36,6% showed systolic flattening of mitral leaflets. CONCLUSIONS: ST depression in asymptomatic menopausal female athletes is frequent and it is characterized by a specific presentation pattern. This is particularly important in the menopausal age when CV risk factors are more prevalent.

Development of a sports specific aerobic capacity test for karate - a pilot study.

The purpose of the study was to develop an aerobic fitness assessment test for competitive Karate practitioners and describe the preliminary findings. Five well-trained, competitive Karate practitioners participated in this study. A protocol simulating common attack strikes used in competition Karate sparring was developed from video analysis. In addition, pilot testing established a specific sequence of strikes and timings to be used in the test. The time to perform the strike sequence remained the same, whilst the time between strike sequence performances was progressively reduced. The aim of the test was to increase intensity of exercise through a decrease in recovery. On two separate occasions, absolute and relative peak oxygen uptake (VO2peak), peak ventilation (VEpeak), maximum heart rate (HRM), and time to exhaustion (TE) obtained during the test were recorded. Subjective feedback provided by the participants was positive in that participants felt the test accurately simulated actions of a competitive sparring situation, and as a result athletes felt more motivated to perform well on this test. There was no significant between test difference in absolute VO2peak, relative VO2peak, HRM and TE (p > 0.05), indicating a potentially high reproducibility with the new test for these variables (test 1-test 2 difference of 0.04 L·min(-1), 1 ml·kg(-1)·min(-1), -3 beats·min(-1), and 28 s; respectively). However, VEpeak displayed potentially less reproducibility due to a significant difference observed between tests (test 1- test 2 difference of -2.8 L·min(-1), p < 0.05). There was a significant relationship between TE and relative VO2peak (R(2) = 0.77, p < 0.001). Further developments to the test will need to address issues with work rate/force output assessment/monitoring. The new test accurately simulates the actions of competitive Karate sparring. Key PointsThis is the first attempt at an aerobic fitness test specific to competitive Karate practitionersAnecdotal reports are that the new test accurately simulates the actions used in competition KarateRelative VO2peak was significantly related to time to exhaustion, with 63.5% of the variance in time to exhaustion attributed to relative VO2peak.Test developments include the use of force plates and transducers to assess force/power output during the test.

Prueba de escalón de Mcardle: una ecuación para estimar el Vo2 máx. en estudiantes de educación física / Mcardle step test: an equation for estimating the VO2 max. in physical education students

El objetivo de esta investigación es obtener una ecuación para determinar VO2 máx. a través de una prueba submáxima utilizando la frecuencia cardíaca de recuperación (FCr). Se diseñó en un estudio descriptivo correlacional dentro de un marco cuantitativo y se evaluó a 18 sujetos, 9 damas y 9 varones, de primero a cuarto año estudiantes de educación física con un muestreo de tipo intencional. Se midió la FCr en la prueba submáxima en escalón de McArdle, utilizando el monitor de FC marca Polar mo-delo V800 (Finlandia), y el consumo máximo de oxígeno (VO2 máx.) en el test de esfuerzo máximo de Bruce con el analizador de gases marca COSMED, modelo Fitmate PRO (Italia). En los resultados, la correlación (coeficiente de Pearson) que se obtuvo fue de r = ­0.84 (p<0.001) la cual se encuentra en una categoría considerable, obteniendo la ecuación y = ­0.4132 x + 110.68 con un error de estimación estándar (EEE) de 5.8 ml.kg.min­1.

The main aim of this research is to obtain an equation to determine the VO2 max through a submaximal test using heart rate recovery (HRr). A correlational descriptive study was designed within a quantitati-ve framework, where 18 subjects, all physical education college students, from freshman to senior year, were evaluated (9 females and 9 males), using diversity sampling (intentional). The HRr was measured in the McArdle submaximal step using the HR monitor, Polar V800 model (Finland), and the VO2 max. in the Bruce maximum effort test was measured with the gas analyzer COSMED model Fitmate PRO (Italy). In the results, the correlation (Pearson coefficient) obtained was r = −0.84 (p<0.001) which is within the considerable category, obtaining the equation y = 0.4132 x + 110.68 with a standard error of estimation (SEE) of 5.8 ml.kg.min−1.