Biceps Femoris Long Head Muscle Fascicles Actively Lengthen During the Nordic Hamstring Exercise

Current debate exists around whether a presumed eccentric exercise, the Nordic hamstring exercise (NHE), actually causes active hamstring muscle lengthening. This is because of the decoupling that can occur between the muscle fascicle and muscle-tendon unit (MTU) length changes in relatively compliant human lower-limb MTUs, which results in MTU lengthening not necessarily causing muscle fascicle lengthening. This missing knowledge complicates the interpretation of why the NHE is effective at reducing running-related hamstring muscle injury risk in athletes previously unfamiliar with performing this exercise. The purpose of the study was therefore to investigate if the most-commonly injured hamstring muscle, the biceps femoris long head (BF), exhibits active muscle lengthening (i.e. an eccentric muscle action) during the NHE up until peak force in Nordic novices. External reaction force at the ankle, knee flexion angle, and BF and semitendinosus muscle activities were recorded from the left leg of 14 participants during the NHE. Simultaneously, BF muscle architecture was imaged using B-mode ultrasound imaging, and muscle architecture changes were tracked using two different tracking algorithms. From ~85 to 100% of peak NHE force, both tracking algorithms detected that BF muscle fascicles (n = 10) significantly lengthened (p < 0.01) and had a mean positive lengthening velocity (p ≤ 0.02), while knee extension velocity remained positive (17°·s−1) over knee flexion angles from 53 to 37° and a duration of 1.6 s. Despite some individual cases of brief isometric fascicle behavior and brief fascicle shortening during BF MTU lengthening, the predominant muscle action was eccentric under a relatively high muscle activity level (59% of maximum). Eccentric hamstring muscle action therefore does occur during the NHE in relatively strong (429 N) Nordic novices, which might contribute to the increase in resting BF muscle fascicle length and reduction in running-related injury risk, which have previously been reported following NHE training. Whether an eccentric BF muscle action occurs in individuals accustomed to the NHE remains to be tested

Physical activity in 9–15 year-old pediatric cancer survivors compared to a nationwide sample

Introduction: Sufficient physical activity (PA) has the potential to mitigate late effects of cancer, but objective data of PA levels in adolescents are scarce. The aim of this study was to investigate differences in PA behavior between childhood cancer survivors (CCS) and healthy peers. Methods: PA levels of n = 74 CCS and n = 1304 healthy peers from the MoMo study aged 9–15 years were assessed with validated objective accelerometry and group means were compared. A binary multiple logistic regression was performed to investigate the potential predictors of PA. Results: CCS spent significantly more time sedentary (p < 0.001) and less time in moderate-to-vigorous physical activity (p = 0.002) compared to the healthy cohort. Subgroup analysis revealed the largest deviations of PA levels for CCS aged 9–11 years who fulfilled international PA recommendations on significantly fewer days than MoMo (p < 0.01). Health conditions seem to be a predictor concerning the fulfillment of international PA recommendations by the WHO (p = 0.015). Conclusions: Our study identified vulnerable groups which seem to require targeted exercise and health behavior change programs to increase physical activity and reduce sedentary time. The presence of treatment sequelae as a significant predictor of insufficient physical activity underlines the need of multidisciplinary supportive care approaches

Is an Exercise Program for Pediatric Cancer Patients in Palliative Care Feasible and Supportive?—A Case Series

(1) Background: Growing evidence indicates benefits through exercise programs in pediatric oncology throughout the whole cancer trajectory. This should include palliative care, too. This project analyzes the feasibility of a supervised exercise program offered during hospital and home-based care for children with advanced cancer diagnoses. (2) Methods: Four children (7–13 years old) with advanced cancer diagnoses participated in this project. It consisted of supervised exercise sessions offered once a week (30–90 min), mainly home-based, but also on an in- and outpatient basis. Regular data assessments included psychological and physical capacity-related endpoints and body composition. Details and contents of exercise sessions and adverse events were recorded. (3) Results: Exercise was feasible with 73 ± 9% adherence to the minimum number of planned sessions. The exercise offer was accepted until shortly before death. Effects on fatigue, quality of life and muscular endurance were noted. Participants showed major deviations from age-specific reference values. No exercise-related adverse events occurred. (4) Conclusions: The exercise program was safe, feasible, and might have served as a supportive tool to reduce overall burden. Evaluation of exercise as usual palliative care should be assessed by further studies

Biceps femoris long head muscle fascicles actively lengthen during the nordic hamstring exercise

Current debate exists around whether a presumed eccentric exercise, the Nordic hamstring exercise (NHE), actually causes active hamstring muscle lengthening. This is because of the decoupling that can occur between the muscle fascicle and muscle-tendon unit (MTU) length changes in relatively compliant human lower-limb MTUs, which results in MTU lengthening not necessarily causing muscle fascicle lengthening. This missing knowledge complicates the interpretation of why the NHE is effective at reducing running-related hamstring muscle injury risk in athletes previously unfamiliar with performing this exercise. The purpose of the study was therefore to investigate if the most-commonly injured hamstring muscle, the biceps femoris long head (BF), exhibits active muscle lengthening (i.e. an eccentric muscle action) during the NHE up until peak force in Nordic novices. External reaction force at the ankle, knee flexion angle, and BF and semitendinosus muscle activities were recorded from the left leg of 14 participants during the NHE. Simultaneously, BF muscle architecture was imaged using B-mode ultrasound imaging, and muscle architecture changes were tracked using two different tracking algorithms. From ~85 to 100% of peak NHE force, both tracking algorithms detected that BF muscle fascicles ($\it n$ = 10) significantly lengthened ($\it p$ < 0.01) and had a mean positive lengthening velocity ($\it n$ ≤ 0.02), while knee extension velocity remained positive (17°·s$^{−1}$) over knee flexion angles from 53 to 37° and a duration of 1.6 s. Despite some individual cases of brief isometric fascicle behavior and brief fascicle shortening during BF MTU lengthening, the predominant muscle action was eccentric under a relatively high muscle activity level (59% of maximum). Eccentric hamstring muscle action therefore does occur during the NHE in relatively strong (429 N) Nordic novices, which might contribute to the increase in resting BF muscle fascicle length and reduction in running-related injury risk, which have previously been reported following NHE training. Whether an eccentric BF muscle action occurs in individuals accustomed to the NHE remains to be tested

Design and Evaluation of an Outdoor Exercise Program for Pediatric Cancer Survivors

Exercise programs for young people after cancer are not part of regular oncological care. This study describes and evaluates a regional outdoor exercise program and presents data with regard to the promoting and inhibiting factors for participation among pediatric cancer survivors. Exercise options, number of participants, and the cohort were evaluated descriptively for one year. A self-developed questionnaire was used to evaluate satisfaction, mood, motivations, and barriers to exercise. Overall N = 26 survivors (14.6 &plusmn; 5.5 years) participated in at least one activity in 2019 including try-out days (N = 10) and active weekend camps (N = 2). No adverse events occurred in 302 physical activity hours. Twenty-one survivors participated in the survey. The largest motivational aspect to participate was &ldquo;to try out a new sport&rdquo; (83.9%). Survivors reported &ldquo;good mood&rdquo;, and &lsquo;being happy&rsquo; after exercising. The largest barrier was concern about &lsquo;not being able to keep up with others&rsquo; (38.1%). Around one-third (try-out day) and 50% (active weekend camp) of survivors did not feel confident to continue exercising outside the supervised exercise oncology program. This survey shows high enthusiasm for this exercise program with different outdoor activities and suggests that similar interventions may be accepted by this population

Adverse events during supervised exercise interventions in pediatric oncology - a nationwide survey

Objectives: Exercise interventions during and after treatment for pediatric cancer are associated with beneficial physical, psychological, and social effects. However, valid data about adverse events (AEs) of such interventions have rarely been evaluated. This retrospective study evaluates AEs that occurred during supervised oncological exercise programs for pediatric cancer patients and survivors. Methods: This Germany-wide study used a self-administered online survey focusing on general program characteristics and AEs retrospectively for 2019. The questionnaire included (a) basic data on the offered exercise program, (b) AEs with consequences (Grade 2–5) that occurred in 2019 during an exercise intervention, (c) number of Grade 1 AEs, (d) safety procedures as part of the exercise programs, and (e) possibility to give feedback and describe experience with AEs in free text. Results: Out of 26 eligible exercise programs, response rate of program leaders was 92.3% (n = 24). Representatives working for Universities (n = 6), rehabilitation clinics (n = 3), acute cancer clinics (n = 12), and activity camps (n = 3) participated. In total, 35,110 exercise interventions with varying duration were recorded for 2019. Six AEs with consequences (Grade 2–3) occurred during exercise interventions after cancer treatment resulting in an incidence of 17 per 100,000 exercise interventions (0.017%). No life-threatening consequences or death were reported and no serious AE occurred during acute cancer treatment. Grade 1 AE occurred with a frequency of 983, corresponding to an incidence of 2,800 per 100,000 interventions (2.8%). Most frequent Grade 1 AE were muscle soreness, circulatory problems, and abdominal pain. The most frequent preventive safety procedures at the institutions were regular breaks, consultations with the medical treatment team, and material selection with low injury potential. Conclusions: Supervised exercise interventions for pediatric cancer patients and survivors seem to be safe and AEs with consequences comparatively rare when compared to general childhood population data. Occurrence of grade 1 AEs was common, however, causality was probably not evident between AEs and the exercise intervention. Future research should standardize assessment of AEs in clinical practice and research, and prospectively register and evaluate AEs that occur in the context of exercise interventions in pediatric cancer patients and survivors