Test-retest reliability of the FitMáx©-questionnaire in a clinical and healthy population.

PURPOSE: The FitMáx© was developed as a questionnaire-based instrument to estimate Cardiorespiratory Fitness (CRF) expressed as oxygen uptake at peak exercise (VO2peak). Test-retest reliability is a clinometric measurement property, which defines stability over time if multiple measurements are performed (i.e. reliability). The present study aimed to assess the test-retest reliability of the FitMáx©-questionnaire in different patient groups. PATIENTS AND METHODS: A total of 127 cardiac, pulmonary and oncology patients and healthy subjects aged 19-84 years who completed the questionnaire twice within an average of 18 days were included for analysis. Participants were in a stable clinical situation (no acute disease or participating in a training program). To determine the test-retest reliability, the Intraclass Correlation Coefficient (ICC) and Standard Error of the Measurement (SEM) was calculated between the first (T0) and second (T1) administration of the questionnaires. RESULTS: An excellent agreement was found between the FitMáx©-questionnaire scores at T0 and T1, with an ICC of 0.97 (SEM 1.91) in the total study population and an ICC ranging from 0.93 to 0.98 (SEM 1.52-2.27) in the individual patient groups. CONCLUSION: The FitMáx©-questionnaire proves to be reliable and stable over time to estimate CRF of patients and healthy subjects. Trial registration NTR (Netherlands Trial Register), NL8846. Registered 25 August 2020, https://trialsearch.who.int/Trial2.aspx?TrialID=NL8846.

Multimodal prehabilitation in patients with non-small cell lung cancer undergoing anatomical resection: protocol of a non-randomised feasibility study.

BACKGROUND: The preoperative period can be used to enhance a patient's functional capacity with multimodal prehabilitation and consequently improve and fasten postoperative recovery. Especially, non-small cell lung cancer (NSCLC) surgical patients may benefit from this intervention, since the affected and resected organ is an essential part of the cardiorespiratory fitness. Drafting a prehabilitation programme is challenging, since many disciplines are involved, and time between diagnosis of NSCLC and surgery is limited. We designed a multimodal prehabilitation programme prior to NSCLC surgery and aimed to conduct a study to assess feasibility and indicative evidence of efficacy of this programme. Publication of this protocol may help other healthcare facilities to implement such a programme. METHODS: The multimodal prehabilitation programme consists of an exercise programme, nutritional support, psychological support, smoking cessation, patient empowerment and respiratory optimisation. In two Dutch teaching hospitals, 40 adult patients with proven or suspected NSCLC will be included. In a non-randomised fashion, 20 patients follow the multimodal prehabilitation programme, and 20 will be assessed in the control group, according to patient preference. Assessments will take place at four time points: baseline, the week before surgery, 6 weeks postoperatively and 3 months postoperatively. Feasibility and indicative evidence of efficacy of the prehabilitation programme will be assessed as primary outcomes. DISCUSSION: Since the time between diagnosis of NSCLC and surgery is limited, it is a challenge to implement a prehabilitation programme. This study will assess whether this is feasible, and evidence of efficacy can be found. The non-randomised fashion of the study might result in a selection and confounding bias. However, the control group may help putting the results of the prehabilitation group in perspective. By publishing this protocol, we aim to facilitate others to evaluate and implement a multimodal prehabilitation programme for surgical NSCLC patients. TRIAL REGISTRATION: The current study is registered as NL8080 in the Netherlands Trial Register on the 10th of October 2019, https://www.trialregister.nl/trial/8080 . Secondary identifiers: CCMO (Central Committee on Research Involving Human Subjects) number NL70578.015.19, reference number of the Medical Ethical Review Committee of Máxima MC W19.045.

Monitoring aerobic capacity in cancer survivors using self-reported questionnaires: criterion validity and responsiveness.

BACKGROUND: Evaluating the criterion validity and responsiveness of the self-reported FitMáx©-questionnaire, Duke Activity Status Index (DASI) and Veterans Specific Activity Questionnaire (VSAQ) to monitor aerobic capacity in cancer survivors. METHODS: Cancer survivors participating in a 10-week supervised exercise program were included. The FitMáx©-questionnaire, DASI, VSAQ and a cardiopulmonary exercise test (CPET) were completed before (T0) and after (T1) the program. Intraclass correlation coefficients (ICC) were calculated between VO2peak estimated by the questionnaires (questionnaire-VO2peak) and VO2peak measured during CPET (CPET-VO2peak), at T0 to examine criterion validity, and between changes in questionnaire-VO2peak and CPET-VO2peak (ΔT0-T1) to determine responsiveness. Receiver operating characteristic (ROC) analyses were performed to examine the ability of the questionnaires to detect true improvements (≥ 6%) in CPET-VO2peak. RESULTS: Seventy participants were included. Outcomes at T1 were available for 58 participants (83%). Mean CPET-VO2peak significantly improved at T1 (Δ1.6 mL·kg- 1·min- 1 or 8%). Agreement between questionnaire-VO2peak and CPET-VO2peak at T0 was moderate for the FitMáx©-questionnaire (ICC = 0.69) and VSAQ (ICC = 0.53), and poor for DASI (ICC = 0.36). Poor agreement was found between ΔCPET-VO2peak and Δquestionnaire-VO2peak for all questionnaires (ICC 0.43, 0.19 and 0.18 for the FitMáx©-questionnaire, VSAQ and DASI, respectively). ROC analysis showed that the FitMáx©-questionnaire was able to detect improvements in CPET-VO2peak (area under the curve, AUC = 0.77), when using a cut-off value of 1.0 mL·kg- 1·min- 1, while VSAQ (AUC = 0.66) and DASI (AUC = 0.64) could not. CONCLUSION: The self-reported FitMáx©-questionnaire has sufficient validity to estimate aerobic capacity in cancer survivors at group level. The responsiveness of the FitMáx©-questionnaire for absolute change is limited, but the questionnaire is able to detect whether aerobic capacity improved. The FitMáx©-questionnaire showed substantial better values of validity and responsiveness compared to DASI and VSAQ.

Short- and long-term outcomes after endarterectomy with autologous patching in endurance athletes with iliac artery endofibrosis.

OBJECTIVE: Endurance athletes such as cyclists may develop intermittent claudication owing to iliac artery endofibrosis after long-lasting extreme hemodynamic challenges. This study investigated short-term (<1.5 years) and long-term (>5 years) satisfaction and safety after a surgical endarterectomy and autologous patching. METHODS: Data of endurance athletes who underwent an endarterectomy for flow limitation of the iliac artery owing to endofibrosis between 1997 and 2015 in one center were studied. Maximal cycling exercise tests, ankle-brachial index with flexed hips, echo-Doppler examination (peak systolic velocity), and contrast-enhanced magnetic resonance angiography were performed before and 6 to 18 months after surgery. Short-term and long-term satisfaction were evaluated using questionnaires. Potential patch dilatation was assessed using echo-Doppler. RESULTS: Analysis of 68 patients (79 legs; 55.7% males, median age at the time of surgery, 34 years; interquartile range, 26-41 years) demonstrated that cycling workload at symptom onset improved from 226 ± 97 to 333 ± 101 (P < .001) Watts. Peak workload increased from 326 ± 111 to 352 ± 93 Watts (P < .001). Ankle-brachial index with flexed hips increased from 0.34 (interquartile range [IQR], 0.00-0.47) to 0.59 (IQR, 0.51-0.69; P < .001). Peak systolic velocity with extended and flexed hip decreased from 2.04 m·sec-1 (IQR, 1.52-2.56 m·3sec-1) to 1.25 m·sec-1 (IQR, 0.92-1.62 m·sec-1; P < .001) and 2.40 m·sec-1 (IQR, 1.81-2.81 m·sec-1) to 1.15 m·sec-1 (IQR, 0.97-1.60 m·sec-1; P < .001), respectively. Thirty-day major complication rate was 5.1% (hematoma requiring evacuation nLegs = 2, septic bleeding from deep infection nLegs = 1, and iliac occlusion requiring thrombectomy nLegs = 1). In the short term, 91.2% of patients reported symptom reduction with a 93.7% overall satisfaction rate. After a median of 11.1 years (IQR, 7.8-17.6 years), the overall satisfaction was 91.7%; 94.5% of patients reported persistent symptom reduction. Patch dilatation of >20 mm was observed in two patients. Linear mixed model analysis revealed no alarming patch dilatation in the long term. CONCLUSIONS: Endarterectomy with an autologous patch for intermittent claudication owing to iliac artery endofibrosis in endurance athletes shows high rates of patient satisfaction and symptom reduction in both the short and long term. The risk of surgical complications or patch dilatation is mild. A surgical intervention for flow limitation of the iliac artery owing to endofibrosis is safe and successful.

Surgical shortening of lengthened iliac arteries in endurance athletes: Short-term and long-term satisfaction.

OBJECTIVE: Endurance athletes are prone to develop flow limitations in iliac arteries (FLIA). Especially in cyclists and ice speed skaters, excessive hemodynamic loading coupled with hip hyperflexion may cause kinking in lengthened iliac arteries necessitating surgical correction. This study investigated the short-term (≤1.5 years) and long-term (≥5 years) satisfaction of operative shortening of the iliac artery in endurance athletes. METHODS: All patients who were diagnosed and operated for FLIA owing to lengthened and kinked iliac arteries between 1997 and 2015 in one center were analyzed. Short-term follow-up consisted of an incremental maximal cycling test, ankle-brachial index with flexed hips, echo-Doppler examination with peak systolic velocity measurements and contrast-enhanced magnetic resonance angiography before and 6 to 18 months after surgery. Both short- and long-term satisfaction were assessed using questionnaires. RESULTS: A total of 83 patients (90 operated legs; 96.7% males; median age of 34 years at the time of surgery; interquartile range [IQR], 29-47) were analyzed. In the short-term, 87.5% reported symptom reduction with an 86.4% overall satisfaction rate. Symptom-free cycling improved from 272 ± 84 W to 384 ± 101 W (P < .001), whereas the maximal workload increased from 419 ± 72 W to 428 ± 67 W (P = .01). The ankle-brachial index with flexed hips increased from 0.55 (IQR, 0.45-0.65) to 0.62 (IQR, 0.52-0.74; P = .008), and the peak systolic velocity measured with hips flexed decreased from 2.50 m/s (IQR, 1.77-3.13 m/s) to 1.57 m/s (IQR, 1.20-2.04 m/s; P < .001). After a median of 12 years (IQR, 9.0-15.4 years), symptoms were still decreased in 84.1% of patients with an 81.2% overall satisfaction rate (79.5% response rate). Three patients needed a reintervention (recurrent FLIA, n = 2; failure, n = 1). CONCLUSIONS: Operative shortening of a lengthened and kinked iliac artery causing FLIA is successful both in the short- and long-term.

Diagnosing Sport-Related Flow Limitations in the Iliac Arteries Using Near-Infrared Spectroscopy.

Background: A flow limitation in the iliac arteries (FLIA) in endurance athletes is notoriously difficult to diagnose with the currently available diagnostic tools. At present, a commonly used diagnostic measure is a decrease in ankle brachial index with flex hips (ABIFlexed) following a maximal effort exercise test. Near-infrared spectroscopy (NIRS) is a non-invasive technique that measures skeletal muscle oxygenation as reflected by the balance of O2 delivery from microvascular blood flow and O2 uptake by metabolic activity. Therefore, NIRS potentially serves as a novel technique for diagnosing FLIA. The purpose of this study is to compare the diagnostic accuracy of NIRS-derived absolute, amplitude, and kinetic variables in legs during and after a maximal exercise test with ABIFlexed. Methods: ABIFlexed and NIRS were studied in 33 healthy subjects and 201 patients with FLIA diagnosed with echo-Doppler. Results: After maximal exercise, NIRS kinetic variables, such as the half value time and mean response time, resulted in a range of 0.921 to 0.939 AUC for the diagnosis of FLIA when combined with ABIFlexed. Conversely, ABIFlexed measurements alone conferred significantly worse test characteristics (AUC 0.717, p < 0.001). Conclusions: NIRS may serve as a diagnostic adjunct in patients with possible FLIA.

Construct Validity of the Steep Ramp Test for Assessing Cardiorespiratory Fitness in Patients With Breast Cancer and the Effect of Chemotherapy-Related Symptom Burden.

OBJECTIVE: To investigate the construct validity of the Steep Ramp Test (SRT) by longitudinally comparing the correlation between maximum short exercise capacity of the SRT and direct measurements of peak oxygen consumption (Vo2peak) during or shortly after treatment in patients with breast cancer and the potential effect of chemotherapy-induced symptom burden. DESIGN: Cross-sectional. SETTING: Multicenter. PARTICIPANTS: We used data from 2 studies that included women with breast cancer treated with chemotherapy, resulting in 274 observations. A total of 161 patients (N=161) performed the cardiopulmonary exercise test and the SRT in 2 test sessions on different time points around chemotherapy treatment. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Fatigue was assessed with the Multidimensional Fatigue Inventory, and nausea and vomiting and pain by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30. The longitudinal correlation between the maximum short exercise capacity and Vo2peak was investigated using a linear mixed model. Interaction terms were added to the model to investigate whether the correlation varied by symptom burden. RESULTS: We found a statistically significant moderate correlation between Vo2peak and maximum short exercise capacity (0.61; 95% confidence interval, 0.51-0.70; P<.01) over time. This correlation was slightly attenuated (-0.07; 95% confidence interval, -0.13 to 0.00; P=.04) in patients with chemotherapy-related nausea and vomiting, indicating smaller correlations of Vo2peak with the maximum short exercise capacity with increasing symptom burden. Pain and fatigue did not significantly modify the correlation. CONCLUSIONS: The SRT can only be used as a proxy for changes in aerobic capacity with great caution and with attention for the level of nausea and vomiting.

Estimating VO2peak in 18-90 Year-Old Adults: Development and Validation of the FitMáx©-Questionnaire.

Purpose: Cardiorespiratory fitness (CRF) plays an essential role in health outcomes and quality of life. However, it is often not assessed nor estimated. Objective CRF assessment is costly, labour intensive and not widely available. Patient-reported outcome measures estimate CRF more cost-efficiently, but current questionnaires lack accuracy. The aim of this study is to develop a new self-reported questionnaire to estimate CRF. Materials and Methods: The FitMáx©-questionnaire, consisting of only three questions assessing walking, stair climbing, and cycling capacity, was compared with the commonly used Duke Activity Status Index (DASI) and Veterans Specific Activity Questionnaire (VSAQ). These questionnaires were compared to peak oxygen uptake (VO2peak) as measured with cardiopulmonary exercise testing. This study included 759 cardiac, pulmonary and oncologic patients and healthy persons aged 18‒90. Results: FitMáx© strongly correlated (r = 0.94 (0.92‒0.95) SEE = 4.14 mL∙kg-1∙min-1) with measured VO2peak. Bias between predicted and measured VO2peak was -0.24 (-9.23‒8.75; 95% limits of agreement) mL·kg-1·min-1. The FitMáx© scored superiorly on correlation and SEE compared with the DASI and VSAQ, r = 0.75 (0.68‒0.80) SEE = 4.62 mL∙kg-1∙min-1 and r = 0.87 (0.83‒0.90) SEE = 6.75 mL∙kg-1∙min-1, respectively. Conclusion: FitMáx© is a valid and accessible questionnaire to estimate CRF expressed as VO2peak in clinical practice and shows substantial improvement compared to currently used questionnaires.

Short- and long-term results of operative iliac artery release in endurance athletes.

OBJECTIVE: Endurance athletes can develop intermittent claudication due to sports-related flow limitations of the iliac artery (FLIA) caused by arterial kinking. In the present study, we investigated the short- and long-term efficacy of an operative release for iliac artery kinking. METHODS: Between 1996 and 2015, all patients with a diagnosis of FLIA due to iliac artery kinking without substantial arterial stenosis (<15%) or an excessive arterial length (vessel length to straight ratio, <1.25) who had undergone surgery were included. The short-term follow-up protocol consisted of cycling tests, the ankle brachial index with a flexed hip, and Doppler echography examinations to determine the peak systolic velocity before and 6 to 18 months after surgery. Additionally, the short- and long-term efficacy were evaluated using questionnaires. RESULTS: A total of 142 endurance athletes (155 legs; 88.4% male; median age, 26 years; interquartile range [IQR], 22-31 years) were available for analysis. In the short term, the symptoms had decreased in 83.9% of the patients, with an overall 80.3% satisfaction rate. Power during a maximal cycling test had improved from 420 W (IQR, 378-465 W) to 437 W (IQR, 392-485 W; P < .001). The symptom-free workload had increased from 300 W (IQR, 240-340 W) to 400 W (IQR, 330-448 W; P < .001). The postexercise ankle brachial index with a flexed hip had increased from 0.53 (IQR, 0.40-0.61) to 0.57 (IQR, 0.47-0.64; P = .002), and the peak systolic velocity with a flexed hip had decreased from 1.88 m/s (IQR, 1.45-2.50 m/s) to 1.52 m/s (IQR, 1.19-2.07 m/s; P < .001). Postoperative imaging studies revealed some degree kinking in 33.9%, mostly asymptomatic. The long-term results were evaluated after a median of 15.2 years (IQR, 10.9-19.5 years). The athletes had cycled an additional 125.500 km (IQR, 72.00-227.500 km), which was approximately equal to the 131.000 km (IQR, 98.250-220.000 km) cycled before the diagnosis of FLIA. On the long term, 63.9% of the athletes reported persistent reduction of complaints, with an overall 59.1% satisfaction rate. Eight patients had required reintervention, six because of treatment failure and two because of newly developed FLIA. CONCLUSIONS: Operative iliac artery release for sports-related functional kinking in the absence of stenosis or an excessive vessel length was effective for most athletes in the short and long term.

Test-retest reliability of skeletal muscle oxygenation measurement using near-infrared spectroscopy during exercise in patients with sport-related iliac artery flow limitation.

The ankle-brachial index is an accurate tool for detecting claudication in atherosclerotic patients. However, this technique fails to identify subtle flow limitations of the iliac arteries (FLIA) in endurance athletes. Near-infrared spectroscopy (NIRS) is a noninvasive technique that measures skeletal muscle tissue oxygenation status. The aim of the present study is to examine the absolute and relative test-retest reliability of NIRS and evaluate its potential as a diagnostic tool in FLIA. NIRS-derived exercise variables were analyzed during exercise and recovery in FLIA 17 patients and 19 healthy controls. The relative reliability of absolute variables (such as the maximal value) were slight to yet predominantly substantial (intraclass correlation coefficient [ICC], ICC range: 0.06-0.76) with good to excellent absolute reliability (absolute limits of agreement [ALoA], ALoA range: 0.8 ± 10.2 to 0.7 ± 13.1; coefficient of variation [CV], CV range: 5%-11%). Absolute values encompassing signal amplitudes showed moderate to almost perfect relative reliability (ICC range: 0.51-0.89) and poor to good absolute reliability (ALoA range: -1.3 ± 7.0 to -2.5 ± 15.7; CV range: 15%-32%). Kinetic variables showed moderate to almost perfect relative reliability for most recovery kinetics variables (ICC range: 0.54-0.86) with fair to good absolute reliability (ALoA range: 0.4 ± 12.2 to 3.9 ± 37.9; CV range: 18%-27%). Particularly, kinetic variables showed significant differences between patients and healthy subjects. NIRS is found to be a reliable method for examining muscle tissue oxygenation variables. Given the significant differences in especially recovery kinetics between normal subjects and patients, NIRS may contribute to diagnosing FLIA in endurance athletes.

Physical Activity is Associated with Health Related Quality of Life in Lymphoma Survivors Regardless of Body Mass Index; Results from the Profiles Registry.

BACKGROUND: Being obese and having a sedentary lifestyle is associated with impaired health-related quality of life (HRQoL) among cancer survivors. The aim of the present study is to investigate the combined influence of body mass index (BMI) and physical activity on HRQoL in lymphoma survivors. METHODS: Lymphoma survivors diagnosed between 1999 and 2012 were invited to complete questionnaires about body height and weight, physical activity and HRQoL using the EORTC QLQ-C30. Multivariable analyses were conducted to evaluate the association of BMI and physical activity on HRQoL. RESULTS: 1.339 lymphoma survivors responded (response rate of 72%) of whom 43% had a healthy weight, 41% were overweight and 14% were obese. They spent on average 10 h, on moderate to vigorous physical activity (MVPA) per week. Multivariable linear regression analysis shows that relatively high active survivors reported higher HRQoL scores and less fatigue compared to relatively low active lymphoma survivors, regardless of BMI. CONCLUSION: MVPA was associated with higher HRQoL in lymphoma survivors regardless of BMI. Further studies, are needed to investigate effects of healthy lifestyle changes to improve HRQoL in lymphoma survivors. Research in understanding association of lifestyle factors may guide future support for lymphoma cancer survivors.

The effect of additional protein on lean body mass preservation in post-bariatric surgery patients: a systematic review.

BACKGROUND: As result of bariatric surgery, patients are susceptible to protein deficiency which can result in undesirable lean body mass (LBM) loss. Consumption of high-protein diets or supplements could counteract this, but evidence about the effect is scarce. This paper systematically reviewed the literature to determine the effect of additional protein intake (≥60 g/day) on LBM preservation in post-bariatric patients. METHODS: An electronic search of PubMed, EMBASE and the Cochrane Library was conducted. Studies were included if patients received a high-protein diet or protein supplements for at least one month, and LBM was assessed. The primary outcome was difference in mean LBM loss between the experimental (protein) and control group. Secondary outcomes were differences in body fat mass, total body water, body mass index and resting metabolic rate. RESULTS: Two of the five included studies (n = 223) showed that consumption of proteins resulted in significant LBM preservation. Only one study reported a significant difference in the reduction of body fat mass and resting metabolic rate in favour of a high-protein diet, but none of the studies showed a significant difference in total body water loss or body mass index change between the two groups. CONCLUSIONS: This paper showed inconclusive evidence for LBM preservation due to protein supplementation or a high-protein diet in post-bariatric patients. This outcome might be subjected to certain limitations, including a lack of blinding and a low compliance rate reported in the included studies. More specific and personalized recommendations regarding protein intake may need to be established by high quality research. Studies investigating the quantity (g/day) and quality (whey, casein or soy) of proteins are also needed.

Sport-related femoral artery occlusion detected by near-infrared spectroscopy and pedal power measurements: a case report.

OBJECTIVES: Approximately one in five professional cycling athletes will eventually develop a sport-related vascular problem. However, detecting such flow limitation is a diagnostic challenge as the sensitivity of the currently available standard diagnostic tools is limited. METHODS: Here we present an athlete with exercise-induced pain and weakness of the left leg. During the physical examination, pulsations of the femoral artery were palpable but less prominent. He was analyzed in an ongoing research project aimed at improving methods detecting sport-related leg flow limitations. RESULTS: During functional testing, the ankle-brachial index of the left leg was moderately lowered. However, results of near-infrared spectroscopy and pedal power measurements were largely abnormal suggesting a severe flow limitation. CONCLUSION: Combining post-exercise ankle-brachial index, near-infrared spectroscopy, and pedal power measurements as routine diagnostic functional testing suggested a severe arterial flow inflow limitation. Conventional diagnostics encompassing duplex-Doppler echography and magnetic resonance angiography confirmed a femoral artery occlusion. CLINICAL TRIAL REGISTRATION: https://www.trialregister.nl/ identifier is Trial NL8557.Abbreviations: NIRS: Near-Infrared Spectroscopy; PPM: Pedal Power Measurements; ABI: Ankle Brachial Index; PSV: Peak Systolic Velocity.

Effectiveness of a Low-Calorie Diet for Liver Volume Reduction Prior to Bariatric Surgery: a Systematic Review.

An energy-restricted diet is often prescribed before bariatric surgery to reduce weight and liver volume. While very-low-calorie diets (VLCDs, 450-800 kcal per day) have shown to be effective, the effectiveness of low-calorie diets (LCDs, 800-1500 kcal per day) is less obvious. The objective of this systematic review was to elucidate the effectiveness of LCD on liver volume reduction in patients awaiting bariatric surgery. Eight studies (n = 251) were included describing nine different diets (800-1200 kcal, 2-8 weeks). An LCD was effective in liver volume reduction (12-27%) and weight loss (4-17%), particularly during the first weeks. The LCD showed an acceptable patients' compliance. Based on these findings, an LCD (800-1200 kcal), instead of a VLCD, for 2 to 4 weeks should be preferred.

Making Patients Fit for Surgery: Introducing a Four Pillar Multimodal Prehabilitation Program in Colorectal Cancer.

BACKGROUND: Considering the relation between preoperative functional capacity and postoperative complications, enhancing patients' functional capacity before surgery with a prehabilitation program may facilitate faster recovery and improve quality of life. However, time before surgery is short, mandating a multimodal and high-intensity training approach. This study investigated feasibility and safety of a prehabilitation program for colorectal cancer. METHODS: Multimodal prehabilitation was offered to patients eligible for participation and they were assigned to an intervention or control group by program availability. The prehabilitation program consisted of the following four interventions: in-hospital high-intensity endurance and strength training, high-protein nutrition and supplements, smoking cessation, and psychological support. Program attendance, patient satisfaction, adverse events, and functional capacity were determined. RESULTS: Fifty patients participated in this study (prehabilitation 20, control 30). Program evaluation revealed a high (90%) attendance rate and high level of patient satisfaction. No adverse events occurred. Endurance and/or strength were improved. Eighty-six percent of patients with prehabilitation recovered to their baseline functional capacity 4 weeks postoperatively, 40% in the control group (P < 0.01). CONCLUSIONS: Multimodal prehabilitation including high-intensity training for colorectal cancer patients is feasible, safe, and effective. A randomized controlled trial (NTR5947) was initiated to determine whether prehabilitation may lower morbidity and mortality rates in colorectal surgery.

Pedal power measurement as a diagnostic tool for functional vascular problems.

BACKGROUND: Cyclists with flow limitations in the iliac arteries complain of pain and loss of power. To investigate whether pedal power measurement has added value in diagnosing the underlying cause of flow limitations in the iliac arteries, we explored the sensitivity and specificity of various pedal power measurement variables. Moreover, it was assessed what the added value of pedal power measurement is compared to diagnosis based on the conventional ankle-brachial blood pressure index. METHODS: 25 healthy participants and 45 patients with unilateral arterial flow limitations were recruited. Participants received Echo-Doppler examination to determine the condition of the iliac arteries. Subsequently, participants performed a maximal cycle ergometer test. During the cycling test the exerted left and right pedal power was measured. From these measurements several variables were derived to diagnose arterial flow limitations. A receiver operating characteristics curve based on a predicted cross-validated model was used to select the variable with the highest predictive value and its cut-off value. FINDINGS: The mean power difference between both legs relative to the exerted power at 95% of the maximal power showed the best predictive value with a sensitivity of 0.76 and a specificity of 0.88. Combining the pedal power measurement and ankle-brachial blood pressure index resulted in a sensitivity of 0.91 and a specificity of 0.88. INTERPRETATION: Pedal power measurement improves sensitivity of diagnosis of iliac artery flow limitations, without increasing the burden of clinical investigation to the patients.

Multimodal prehabilitation in colorectal cancer patients to improve functional capacity and reduce postoperative complications: the first international randomized controlled trial for multimodal prehabilitation.

BACKGROUND: Colorectal cancer (CRC) is the second most prevalent type of cancer in the world. Surgery is the only curative option. However, postoperative complications occur in up to 50% of patients and are associated with higher morbidity and mortality rates, lower health related quality of life (HRQoL) and increased expenditure in health care. The number and severity of complications are closely related to preoperative functional capacity, nutritional state, psychological state, and smoking behavior. Traditional approaches have targeted the postoperative period for rehabilitation and lifestyle changes. However, recent evidence shows that the preoperative period might be the optimal moment for intervention. This study will determine the impact of multimodal prehabilitation on patients' functional capacity and postoperative complications. METHODS/DESIGN: This international multicenter, prospective, randomized controlled trial will include 714 patients undergoing colorectal surgery for cancer. Patients will be allocated to the intervention group, which will receive 4 weeks of prehabilitation (group 1, prehab), or the control group, which will receive no prehabilitation (group 2, no prehab). Both groups will receive perioperative care in accordance with the enhanced recovery after surgery (ERAS) guidelines. The primary outcomes for measurement will be functional capacity (as assessed using the six-minute walk test (6MWT)) and postoperative status determined with the Comprehensive Complication Index (CCI). Secondary outcomes will include HRQoL, length of hospital stay (LOS) and a cost-effectiveness analysis. DISCUSSION: Multimodal prehabilitation is expected to enhance patients' functional capacity and to reduce postoperative complications. It may therefore result in increased survival and improved HRQoL. This is the first international multicenter study investigating multimodal prehabilitation for patients undergoing colorectal surgery for cancer. TRIAL REGISTRATION: Trial Registry: NTR5947 - date of registration: 1 August 2016.

Protease-activated receptors are potential regulators in the development of arterial endofibrosis in high-performance athletes.

OBJECTIVE: High-performance athletes can develop symptomatic arterial flow restriction during exercise caused by endofibrosis. The pathogenesis is poorly understood; however, coagulation enzymes, such as tissue factor (TF) and coagulation factor Xa, might contribute to the fibrotic process, which is mainly regulated through activation of protease-activated receptors (PARs). Therefore, the aim of this explorative study was to evaluate the presence of coagulation factors and PARs in endofibrotic tissue, which might be indicative of their potential role in the natural development of endofibrosis. METHODS: External iliac arterial specimens with endofibrosis (n = 19) were collected during surgical interventions. As control, arterial segments of the external iliac artery (n = 20) were collected post mortem from individuals with no medical history of cardiovascular disease who donated their body to medical science. Arteries were paraffinized and cut in tissue sections for immunohistochemical analysis. Positive staining within lesions was determined with ImageJ software (National Institutes of Health, Bethesda, Md). RESULTS: Endofibrotic segments contained a neointima, causing intraluminal stenosis, which was highly positive for collagen (+150%; P < .01) and elastin (+148%; P < .01) in comparison with controls. Intriguingly, endofibrosis was not limited to the intima because collagen (+213%) and elastin (+215%) were also significantly elevated in the media layer of endofibrotic segments. These findings were accompanied by significantly increased α-smooth muscle actin-positive cells, morphologically compatible with the presence of myofibroblasts. In addition, PAR1 and PAR4 and the membrane receptor TF were increased as well as coagulation factor X. CONCLUSIONS: We showed that myofibroblasts and the accompanying collagen and elastin synthesis might be key factors in the development of endofibrosis. The special association with increased presence of PARs, factor X, and TF suggests that protease-mediated cell signaling could be a contributing component in the mechanisms leading to endofibrosis.

Does vibration superimposed on low-level isometric contraction alter motor unit recruitment strategy?

OBJECTIVE: Beneficial effects, including improved muscle strength and power performance, have been observed during vibration exercise (VE) and partially ascribed to a specific reflex mechanism referred to as Tonic vibration reflex (TVR). TVR involves motor unit (MU) activation synchronized and un-synchronized with the vibration cycle; this suggests VE to alter the temporal MU recruitment strategy. However, the effects of VE on MU recruitment remain poorly understood. This study aims to elucidate the influence of VE on MU recruitment indirectly, by investigating the effects of low-intensity VE on muscle activation. APPROACH: Twenty volunteers performed isometric contractions on the biceps brachii of the right arm at a baseline (low) force equal to 30% of the maximum voluntary contraction without vibration (control) and with vibration at 20, 30, 40, and 55 Hz. Three vibration amplitudes were employed at 12.5%, 25%, and 50% of the baseline. Mean muscle-fiber conduction velocity (mCV), mean frequency (MF), and root mean square (RMS) value were estimated from surface electromyography as indicators of the alteration in MU recruitment strategies. MAIN RESULTS: The mCV estimates during VE were significantly (p < 0.05) higher compared to the control condition. Furthermore, six VE conditions produced significantly larger RMS values compared to control condition. The estimated MF did not show any consistent trend. SIGNIFICANCE: These results suggest that vibration superimposed on low-level isometric contraction alters the MU recruitment strategy, activating larger and faster MUs.