Effects of heavy-load strength training during (neo-)adjuvant chemotherapy on muscle strength, muscle fiber size, myonuclei, and satellite cells in women with breast cancer.

To investigate the effects of heavy-load strength training during (neo-)adjuvant chemotherapy in women with breast cancer on muscle strength, body composition, muscle fiber size, satellite cells, and myonuclei. Women with stage I-III breast cancer were randomly assigned to a strength training group (ST, n = 23) performing supervised heavy-load strength training twice a week during chemotherapy, or a usual care control group (CON, n = 17). Muscle strength and body composition were measured and biopsies from m. vastus lateralis collected before the first cycle of chemotherapy (T0) and after chemotherapy and training (T1). Muscle strength increased significantly more in ST than in CON in chest-press (ST: +10 ± 8%, p < .001, CON: -3 ± 5%, p = .023) and leg-press (ST: +11 ± 8%, p < .001, CON: +3 ± 6%, p = .137). Both groups reduced fat-free mass (ST: -4.9 ± 4.0%, p < .001, CON: -5.2 ± 4.9%, p = .004), and increased fat mass (ST: +15.3 ± 16.5%, p < .001, CON: +16.3 ± 19.8%, p = .015) with no significant differences between groups. No significant changes from T0 to T1 and no significant differences between groups were observed in muscle fiber size. For myonuclei per fiber a non-statistically significant increase in CON and a non-statistically significant decrease in ST in type I fibers tended (p = .053) to be different between groups. Satellite cells tended to decrease in ST (type I: -14 ± 36%, p = .097, type II: -9 ± 55%, p = .084), with no changes in CON and no differences between groups. Strength training during chemotherapy improved muscle strength but did not significantly affect body composition, muscle fiber size, numbers of satellite cells, and myonuclei compared to usual care.

The intensity paradox: A systematic review and meta-analysis of its impact on the cardiorespiratory fitness of older adults.

AIM: The present systematic review and meta-analysis aimed to compare the effect of moderate- versus high-intensity aerobic exercise on cardiorespiratory fitness (CRF) in older adults, taking into account the volume of exercise completed. METHODS: The databases MEDLINE (Ovid), EMBASE (Ovid), and CENTRAL (Cochrane Library) were searched to identify randomized controlled trials (RCTs). Two reviewers extracted data and assessed bias. Comprehensive Meta-Analysis software calculated overall effect size, intensity differences, and performed meta-regression analyses using pre-to-post intervention or change scores of peak oxygen uptake (V̇O2 peak). The review included 23 RCTs with 1332 older adults (intervention group: n = 932; control group: n = 400), divided into moderate-intensity (435 older adults) and high-intensity (476 older adults) groups. RESULTS: Meta-regression analysis showed a moderate, but not significant, relationship between exercise intensity and improvements in V̇O2 peak after accounting for the completed exercise volume (ß = 0.31, 95% CI = [-0.04; 0.67]). Additionally, studies comparing moderate- versus high-intensity revealed a small, but not significant, effect in favor of high-intensity (Hedges' g = 0.20, 95% CI = [-0.02; 0.41]). Finally, no significant differences in V̇O2 peak improvements were found across exercise groups employing various methods, modalities, and intensity monitoring strategies. CONCLUSION: Findings challenge the notion that high-intensity exercise is inherently superior and indicate that regular aerobic exercise, irrespective of the specific approach and intensity, provides the primary benefits to CRF in older adults. Future RCTs should prioritize valid and reliable methodologies for monitoring and reporting exercise volume and adherence among older adults.

Dropout from exercise trials among cancer survivors-An individual patient data meta-analysis from the POLARIS study.

INTRODUCTION: The number of randomized controlled trials (RCTs) investigating the effects of exercise among cancer survivors has increased in recent years; however, participants dropping out of the trials are rarely described. The objective of the present study was to assess which combinations of participant and exercise program characteristics were associated with dropout from the exercise arms of RCTs among cancer survivors. METHODS: This study used data collected in the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) study, an international database of RCTs investigating the effects of exercise among cancer survivors. Thirty-four exercise trials, with a total of 2467 patients without metastatic disease randomized to an exercise arm were included. Harmonized studies included a pre and a posttest, and participants were classified as dropouts when missing all assessments at the post-intervention test. Subgroups were identified with a conditional inference tree. RESULTS: Overall, 9.6% of the participants dropped out. Five subgroups were identified in the conditional inference tree based on four significant associations with dropout. Most dropout was observed for participants with BMI >28.4 kg/m2 , performing supervised resistance or unsupervised mixed exercise (19.8% dropout) or had low-medium education and performed aerobic or supervised mixed exercise (13.5%). The lowest dropout was found for participants with BMI >28.4 kg/m2 and high education performing aerobic or supervised mixed exercise (5.1%), and participants with BMI ≤28.4 kg/m2 exercising during (5.2%) or post (9.5%) treatment. CONCLUSIONS: There are several systematic differences between cancer survivors completing and dropping out from exercise trials, possibly affecting the external validity of exercise effects.

School-based physical activity in relation to active travel - a cluster randomized controlled trial among adolescents enrolled in the school in motion study in Norway.

BACKGROUND: Active travel and school settings are considered ideal for promoting physical activity. However, previous research suggests limited effect of school-based interventions on overall physical activity levels among adolescents. The relationship between physical activity in different domains remains inconclusive. In this study, we examined the effects of adding two weekly hours of school-based physical activity on active travel rates. METHOD: We analyzed data from 1370 pupils in the 9th-grade participating in the cluster RCT; the School In Motion (ScIM) project. Intervention schools (n = 19) implemented 120 min of class-scheduled physical activity and physical education, in addition to the normal 2 hours of weekly physical education in the control schools (n = 9), for 9 months. Active travel was defined as pupils who reported walking or cycling to school, while motorized travel was defined as pupils who commuted by bus or car, during the spring/summer half of the year (April-September), or autumn/winter (October-February). The participants were categorized based on their travel mode from pretest to posttest as; maintained active or motorized travel ("No change"), changing to active travel (motorized-active), or changing to motorized travel (active-motorized). Multilevel logistic regression was used to analyze the intervention effect on travel mode. RESULTS: During the intervention period, most participants maintained their travel habits. In total, 91% of pupils maintained their travel mode to school. Only 6% of pupils switched to motorized travel and 3% switched to active travel, with small variations according to season and trip direction. The intervention did not seem to influence the likelihood of changing travel mode. The odds ratios for changing travel habits in spring/summer season were from active to motorized travel 1.19 [95%CI: 0.53-2.15] and changing from motorized to active travel 1.18 [0.30-2.62], compared to the "No change" group. These findings were consistent to and from school, and for the autumn/winter season. CONCLUSION: The extra school-based physical activity does not seem to affect rates of active travel among adolescents in the ScIM project. TRIAL REGISTRATION: Clinicaltrials.gov ID nr: NCT03817047. Registered 01/25/2019' retrospectively registered'.

Cost-effectiveness of different exercise intensities during oncological treatment in the Phys-Can RCT.

BACKGROUND: Cost-effectiveness is important in the prioritisation between interventions in health care. Exercise is cost-effective compared to usual care during oncological treatment; however, the significance of exercise intensity to the cost-effectiveness is unclear. In the present study, we aimed to evaluate the long-term cost-effectiveness of the randomised controlled trial Phys-Can, a six-month exercise programme of high (HI) or low-to-moderate intensity (LMI) during (neo)adjuvant oncological treatment. METHODS: A cost-effectiveness analysis was performed, based on 189 participants with breast, colorectal, or prostate cancer (HI: n = 99 and LMI: n = 90) from the Phys-Can RCT in Sweden. Costs were estimated from a societal perspective, and included cost of the exercise intervention, health care utilisation and productivity loss. Health outcomes were assessed as quality-adjusted life-years (QALYs), using EQ-5D-5L at baseline, post intervention and 12 months after the completion of the intervention. RESULTS: At 12-month follow-up after the intervention, the total cost per participant did not differ significantly between HI (€27,314) and LMI exercise (€29,788). There was no significant difference in health outcome between the intensity groups. On average HI generated 1.190 QALYs and LMI 1.185 QALYs. The mean incremental cost-effectiveness ratio indicated that HI was cost effective compared with LMI, but the uncertainty was large. CONCLUSIONS: We conclude that HI and LMI exercise have similar costs and effects during oncological treatment. Hence, based on cost-effectiveness, we suggest that decision makers and clinicians can consider implementing both HI and LMI exercise programmes and recommend either intensity to the patients with cancer during oncological treatment to facilitate improvement of health.

Reallocating sedentary time to physical activity: effects on fatigue and quality of life in patients with breast cancer in the Phys-Can project.

PURPOSE: We aimed to investigate the effects of reallocating sedentary time to an equal amount of light (LPA) or moderate-to-vigorous intensity physical activity (MVPA) on cancer-related fatigue and health-related quality of life (HRQoL) in patients with breast cancer. We also aimed to determine the daily amount of sedentary time needed to be reallocated to LPA or MVPA to produce minimal clinically important changes in these outcomes. METHODS: Pooled baseline data from three studies were used, including women with breast cancer who participated in the Phys-Can project. Fatigue was assessed with the Multidimensional Fatigue Inventory questionnaire (MFI; five dimensions, 4-20 scale) and HRQoL with the European Organisation for Research and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30; 0-100 scale). Sedentary time and physical activity were measured with accelerometry. Isotemporal substitution modelling was used for the analyses. RESULTS: Overall, 436 participants (mean age 56 years, fatigue 11 [MFI], HRQoL 66 [EORTC QLQ-C30], LPA 254 min/day, MVPA 71 min/day) were included. Fatigue significantly decreased in two MFI dimensions when reallocating 30 min/day of sedentary time to LPA: reduced motivation and reduced activity (ß = - 0.21). Fatigue significantly decreased in three MFI dimensions when reallocating 30 min/day of sedentary time to MVPA: general fatigue (ß = - 0.34), physical fatigue (ß = - 0.47) and reduced activity (ß = - 0.48). To produce minimal clinically important changes in fatigue (- 2 points on MFI), the amount of sedentary time needed to be reallocated to LPA was ≈290 min/day and to MVPA was ≥ 125 min/day. No significant effects were observed on HRQoL when reallocating sedentary time to LPA or MVPA. CONCLUSIONS: Our results suggest that reallocating sedentary time to LPA or MVPA has beneficial effects on cancer-related fatigue in patients with breast cancer, with MVPA having the greatest impact. In relatively healthy and physically active breast cancer populations, a large amount of time reallocation is needed to produce clinically important changes. Future studies are warranted to evaluate such effects in broader cancer populations. TRIAL REGISTRATION: NCT02473003 (10/10/2014) and NCT04586517 (14/10/2020).

Pre-treatment levels of inflammatory markers and chemotherapy completion rates in patients with early-stage breast cancer.

BACKGROUND: Chemotherapy efficacy is largely dependent on treatment adherence, defined by the relative dose intensity (RDI). Identification of new modifiable risk factors associated with low RDI might improve chemotherapy delivery. Here, we evaluated the association between low RDI and pre-chemotherapy factors, including patient- and treatment-related characteristics and markers of inflammation. METHODS: This exploratory analysis assessed data from 267 patients with early-stage breast cancer scheduled to undergo (neo-)adjuvant chemotherapy included in the Physical training and Cancer (Phys-Can) trial. The association between low RDI, defined as < 85%, patient-related (age, body mass index, co-morbid condition, body surface area) and treatment-related factors (cancer stage, receptor status, chemotherapy duration, chemotherapy dose, granulocyte colony-stimulating factor) was investigated. Analyses further included the association between RDI and pre-chemotherapy levels of interleukin (IL)-6, IL-8, IL-10, C-reactive protein (CRP) and Tumor Necrosis Factor-alpha (TNF-α) in 172 patients with available blood samples. RESULTS: An RDI of < 85% occurred in 31 patients (12%). Univariable analysis revealed a significant association with a chemotherapy duration above 20 weeks (p < 0.001), chemotherapy dose (p = 0.006), pre-chemotherapy IL-8 (OR 1.61; 95% CI (1.01; 2.58); p = 0.040) and TNF-α (OR 2.2 (1.17; 4.53); p = 0.019). In multivariable analyses, inflammatory cytokines were significant association with low RDI for IL-8 (OR: 1.65 [0.99; 2.69]; p = 0.044) and TNF-α (OR 2.95 [1.41; 7.19]; p = 0.007). CONCLUSIONS: This exploratory analysis highlights the association of pre-chemotherapy IL-8 and TNF-α with low RDI of chemotherapy for breast cancer. IL-8 and TNF-α may therefore potentially help to identify patients at risk for experiencing dose reductions. Clinical trial number NCT02473003 (registration: June 16, 2015).

Long-term resource utilisation and associated costs of exercise during (neo)adjuvant oncological treatment: the Phys-Can project.

BACKGROUND: Exercise during oncological treatment is beneficial to patient health and can counteract the side effects of treatment. Knowledge of the societal costs associated with an exercise intervention, however, is limited. The aims of the present study were to evaluate the long-term resource utilisation and societal costs of an exercise intervention conducted during (neo)adjuvant oncological treatment in a randomised control trial (RCT) versus usual care (UC), and to compare high-intensity (HI) versus low-to-moderate intensity (LMI) exercise in the RCT. METHODS: We used data from the Physical Training and Cancer (Phys-Can) project. In the RCT, 577 participants were randomised to HI or to LMI of combined endurance and resistance training for 6 months, during oncological treatment. The project also included 89 participants with UC in a longitudinal observational study. We measured at baseline and after 18 months. Resource utilisation and costs of the exercise intervention, health care, and productivity loss were compared using analyses of covariance (RCT vs. UC) and t test (HI vs. LMI). RESULTS: Complete data were available for 619 participants (RCT HI: n = 269, LMI: n = 265, and UC: n = 85). We found no difference in total societal costs between the exercise intervention groups in the RCT and UC. However, participants in the RCT had lower rates of disability pension days (p < .001), corresponding costs (p = .001), and pharmacy costs (p = .018) than the UC group. Nor did we find differences in resource utilisation or costs between HI and LMI exercise int the RCT. CONCLUSION: Our study showed no difference in total societal costs between the comprehensive exercise intervention and UC or between the exercise intensities. This suggests that exercise, with its well-documented health benefits during oncological treatment, produces neither additional costs nor savings.

Who makes it all the way? Participants vs. decliners, and completers vs. drop-outs, in a 6-month exercise trial during cancer treatment. Results from the Phys-Can RCT.

PURPOSE: To compare sociodemographic, health- and exercise-related characteristics of participants vs. decliners, and completers vs. drop-outs, in an exercise intervention trial during cancer treatment. METHODS: Patients with newly diagnosed breast, prostate, or colorectal cancer were invited to participate in a 6-month exercise intervention. Background data for all respondents (n = 2051) were collected at baseline by questionnaire and medical records. Additional data were collected using an extended questionnaire, physical activity monitors, and fitness testing for trial participants (n = 577). Moreover, a sub-group of decliners (n = 436) consented to additional data collection by an extended questionnaire . Data were analyzed for between-group differences using independent t-tests and chi2-tests. RESULTS: Trial participants were younger (59 ± 12yrs vs. 64 ± 11yrs, p < .001), more likely to be women (80% vs. 75%, p = .012), and scheduled for chemotherapy treatment (54% vs. 34%, p < .001), compared to decliners (n = 1391). A greater proportion had university education (60% vs 40%, p < .001), reported higher anxiety and fatigue, higher exercise self-efficacy and outcome expectations, and less kinesiophobia at baseline compared to decliners. A greater proportion of trial participants were classified as 'not physically active' at baseline; however, within the group who participated, being "physically active" at baseline was associated with trial completion. Completers (n = 410) also reported less kinesiophobia than drop-outs (n = 167). CONCLUSION: The recruitment procedures used in comprehensive oncology exercise trials should specifically address barriers for participation among men, patients without university education and older patients. Individualized efforts should be made to enroll patients with low exercise self-efficacy and low outcome expectations of exercise. To retain participants in an ongoing exercise intervention, extra support may be needed for patients with kinesiophobia and those lacking health-enhancing exercise habits at baseline.

Effectiveness of individualized training based on force-velocity profiling on physical function in older men.

The study aimed to investigate the effectiveness of an individualized power training program based on force-velocity (FV) profiling on physical function, muscle morphology, and neuromuscular adaptations in older men. Forty-nine healthy men (68 ± 5 years) completed a 10-week training period to enhance muscular power. They were randomized to either a generic power training group (GPT) or an individualized power training group (IPT). Unlike generic training, individualized training was based on low- or high-resistance exercises, from an initial force-velocity profile. Lower-limb FV profile was measured in a pneumatic leg-press, and physical function was assessed as timed up-and-go time (TUG), sit-to-stand power, grip strength, and stair-climbing time (loaded [20kg] and unloaded). Vastus lateralis morphology was measured with ultrasonography. Rate of force development (RFD) and rate of myoelectric activity (RMA) were measured during an isometric knee extension. The GPT group improved loaded stair-climbing time (6.3 ± 3.8 vs. 2.3% ± 7.3%, p = 0.04) more than IPT. Both groups improved stair-climbing time, sit to stand, and leg press power, grip strength, muscle thickness, pennation angle, fascicle length, and RMA from baseline (p < 0.05). Only GPT increased loaded stair-climbing time and RFD (p < 0.05). An individualized power training program based on FV profiling did not improve physical function to a greater degree than generic power training. A generic power training approach combining both heavy and low loads might be advantageous through eliciting both force- and velocity-related neuromuscular adaptions with a concomitant increase in muscular power and physical function in older men.

Nurse-led consultations reinforced with eHealth technology: a qualitative study of the experiences of patients with gynecological cancer.

BACKGROUND: During the last decade, the health care profession has moved toward personalized care and has focused on the diversity of survivorship needs after initial cancer treatment. Health care providers encourage empowering patients to participate actively in their own health management and survivorship. Consequently, we developed and piloted a new follow-up model for patients at a Norwegian hospital, referred to as the Lifestyle and Empowerment Techniques in Survivorship of Gynecologic Oncology (LETSGO) model. Using LETSGO, a dedicated nurse replaces the physician in every second follow-up consultation, providing patients who have undergone cancer treatment with self-management techniques that are reinforced with eHealth technology via a specially designed app. Encouraging behavioral change and evaluating the late effects of treatment and recurrence symptoms are central components of self-management techniques. In addition, the app encourages physical activity and positive lifestyle changes, helps identify recurrence-related symptoms, and provides reminders of activity goals. This study aims to investigate experiences with nurse-led consultations supported by eHealth technology among the patients who piloted the LETSGO intervention. METHODS: Semi-structured qualitative interviews were conducted to analyze the participants' experiences with the LETSGO intervention after six to seven months. RESULTS: The participants in the LETSGO pilot felt safe and well cared for. They thought the nurse was less busy than the doctors appear to be, which made it easy for them to share any cancer-related challenges. Many participants reported increased empowerment and confidence in recognizing symptoms of cancer recurrence, and participants who used the app regularly were motivated to increase their physical activity levels. However, the participants also experienced some limitations and technical errors with the app. CONCLUSIONS: Generally, the participants positively received the nurse-led consultations and eHealth technology, but an intervention study is required for further evaluation. In addition, the reported technical app errors should be resolved and tested prior to eHealth application implementation. Regardless, this study may be useful in planning personalized survivorship care studies. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03453788 . Registration March 5, 2018.

Effect of self-regulatory behaviour change techniques and predictors of physical activity maintenance in cancer survivors: a 12-month follow-up of the Phys-Can RCT.

BACKGROUND: Current knowledge about the promotion of long-term physical activity (PA) maintenance in cancer survivors is limited. The aims of this study were to 1) determine the effect of self-regulatory BCTs on long-term PA maintenance, and 2) identify predictors of long-term PA maintenance in cancer survivors 12 months after participating in a six-month exercise intervention during cancer treatment. METHODS: In a multicentre study with a 2 × 2 factorial design, the Phys-Can RCT, 577 participants with curable breast, colorectal or prostate cancer and starting their cancer treatment, were randomized to high intensity exercise with or without self-regulatory behaviour change techniques (BCTs; e.g. goal-setting and self-monitoring) or low-to-moderate intensity exercise with or without self-regulatory BCTs. Participants' level of PA was assessed at the end of the exercise intervention and 12 months later (i.e. 12-month follow-up), using a PA monitor and a PA diary. Participants were categorized as either maintainers (change in minutes/week of aerobic PA ≥ 0 and/or change in number of sessions/week of resistance training ≥0) or non-maintainers. Data on potential predictors were collected at baseline and at the end of the exercise intervention. Multiple logistic regression analyses were performed to answer both research questions. RESULTS: A total of 301 participants (52%) completed the data assessments. A main effect of BCTs on PA maintenance was found (OR = 1.80, 95%CI [1.05-3.08]) at 12-month follow-up. Participants reporting higher health-related quality-of-life (HRQoL) (OR = 1.03, 95%CI [1.00-1.06] and higher exercise motivation (OR = 1.02, 95%CI [1.00-1.04]) at baseline were more likely to maintain PA levels at 12-month follow-up. Participants with higher exercise expectations (OR = 0.88, 95%CI [0.78-0.99]) and a history of tobacco use at baseline (OR = 0.43, 95%CI [0.21-0.86]) were less likely to maintain PA levels at 12-month follow-up. Finally, participants with greater BMI increases over the course of the exercise intervention (OR = 0.63, 95%CI [0.44-0.90]) were less likely to maintain their PA levels at 12-month follow-up. CONCLUSIONS: Self-regulatory BCTs improved PA maintenance at 12-month follow-up and can be recommended to cancer survivors for long-term PA maintenance. Such support should be considered especially for patients with low HRQoL, low exercise motivation, high exercise expectations or with a history of tobacco use at the start of their cancer treatment, as well as for those gaining weight during their treatment. However, more experimental studies are needed to investigate the efficacy of individual or combinations of BCTs in broader clinical populations. TRIAL REGISTRATION: NCT02473003 (10/10/2014).

Is it safe to exercise during oncological treatment? A study of adverse events during endurance and resistance training - data from the Phys-Can study.

INTRODUCTION: Few studies have systematically evaluated the risk of adverse events (AEs) among persons exercising during oncological treatment. We aimed to describe incidence and types of AEs during exercise for persons undergoing oncological treatment, and associations to exercise intensity, exercise adherence, chemotherapy treatment, initial aerobic fitness. A second aim was to compare incidence of lymphedema, periphery inserted central catheter (PICC) complications, and other new medical conditions (any illness or injury occurred during the exercise trial) between high-intensity vs low-to-moderate exercise and usual care (UC). METHODS: This descriptive, comparative study was based on data from an observational study including patients in an UC setting (n = 90) and a randomized exercise trial (n = 577) in which participants exercised at high-intensity (HI) or low-moderate intensity (LMI). Persons with breast, prostate, or colorectal cancer undergoing neo/adjuvant treatment were included. AEs were reported by exercise coaches, participants, and identified in medical records, as were lymphedema, PICC-complications, and new medical conditions. RESULTS: Coaches reported AEs for 20% of the participants, while 28% of participants self-reported AEs. The most common coach- and participant reported AEs were musculoskeletal and the majority (97%) were considered minor. HI had higher likelihood of AEs than LMI, according to both coaches (OR: 1.9 [95%CI 1.16-3.21], p=.011) and participants (OR: 3.36 [95%CI 2.00-5.62], ≤.001). Lymphedema rates were low (4-9%) and PICC complications ranged from 15% in LMI to 23% in UC and there were no statistically significant differences between HI, LMI, and UC. There were no statistically significant differences between HI and LMI regarding new medical conditions. CONCLUSIONS: Exercise during treatment is safe for these patient groups in this setting, even HI exercise can be recommended if no medical contraindications are present. Similar to healthy populations, a higher risk of having minor AEs when exercising at HI in comparison to LMI may exist.

Motivation for physical activity in adolescents with asthma.

OBJECTIVE: We explored motivation for physical activity (PA) and exercise in adolescents with asthma who entered and continued a 10-week play-based exercise intervention. METHODS: Eighteen adolescents with asthma, aged 13-17 years, participated in a 10-week play- and interval-based indoor exercise intervention during winter and autumn months. Semi-structured focus group interviews were conducted in weeks 2 and 8, focusing on motivation for PA and exercise, as well as field observations of exercise sessions in weeks 2, 6, and 8. The first interview was analyzed separately from the second one and descriptive observational data were obtained using thematic analysis and self-determination theory as a framework. RESULTS: In the first round of focus group interviews, participants (n = 18) described amotivation and motivation for PA within the following five themes: "teachers' lack of asthma knowledge", "embarrassment over asthma symptoms", "not being able to keep pace with peers", "seasonal challenges", and "mastering fun physical activities". Based on the second interview (n = 14) and descriptive observational data (n = 18), participants reported and revealed amotivation and motivation for PA within the following four themes: "understanding and relatedness", "social support", "competition", and "mastering fun activities". CONCLUSION: We conclude that play-based exercises designed for groups of adolescents with asthma can support motivation for PA and exercise and reduce social and asthma-specific barriers.

Physical activity and sedentary time in children and adolescents with asthma: A systematic review and meta-analysis.

The influence of asthma on physical activity (PA) in youth remains equivocal. This review synthesizes the evidence regarding the influence of asthma on PA and sedentary time and evaluates the role of key moderators for this relationship. In accordance with PRISMA guidelines, six electronic databases and gray literature were searched. Primary studies in English were included if they reported device-assessed PA in youth with and without asthma. Random effects meta-analyses examined the effect of asthma on PA and, separately, sedentary time. Mixed-effect meta-regression analyses were conducted using age and sex as moderators, with sub-group comparisons for study quality and asthma diagnosis criteria. Overall, of 3944 citations retrieved, 2850 were screened after the removal of supplication and 2743 citations excluded. Of the 107 full-text publications reviewed, 16 were included in data extraction and analysis, with 15 and five studies included in the PA and sedentary time meta-analyses, respectively. The robust effect size estimate for the influence of asthma on PA and sedentary time was -0.04 [95% CI = -0.11, 0.03] and -0.09 [95% CI = -0.12, -0.06], indicating a non-significant and significant trivial effect, respectively. The effect of asthma on PA levels or sedentary time was not associated with age or sex. Youth with controlled asthma are equally physically (in)active as their healthy peers, with asthma associated with less sedentary time. However, methodological limitations and a paucity of clear methodological reporting temper these conclusions. More rigorous device-based assessments, with a particular focus on sedentary time, and more robust diagnoses of asthma, especially with regard to severity, are needed.

Frequent blood flow restricted training not to failure and to failure induces similar gains in myonuclei and muscle mass.

The purpose of the present study was to compare the effects of short-term high-frequency failure vs non-failure blood flow-restricted resistance exercise (BFRRE) on changes in satellite cells (SCs), myonuclei, muscle size, and strength. Seventeen untrained men performed four sets of BFRRE to failure (Failure) with one leg and not to failure (Non-failure; 30-15-15-15 repetitions) with the other leg using knee-extensions at 20% of one repetition maximum (1RM). Fourteen sessions were distributed over two 5-day blocks, separated by a 10-day rest period. Muscle samples obtained before, at mid-training, and 10-day post-intervention (Post10) were analyzed for muscle fiber area (MFA), myonuclei, and SC. Muscle size and echo intensity of m.rectus femoris (RF) and m.vastus lateralis (VL) were measured by ultrasonography, and knee extension strength with 1RM and maximal isometric contraction (MVC) up until Post24. Both protocols increased myonuclear numbers in type-1 (12%-17%) and type-2 fibers (20%-23%), and SC in type-1 (92%-134%) and type-2 fibers (23%-48%) at Post10 (p < 0.05). RF and VL size increased by 5%-10% in both legs at Post10 to Post24, whereas the MFA of type-1 fibers in Failure was decreased at Post10 (-10 ± 16%; p = 0.02). Echo intensity increased by ~20% in both legs during Block1 (p < 0.001) and was ~8 to 11% below baseline at Post24 (p = 0.001-0.002). MVC and 1RM decreased by 5%-10% after Block1, but increased in both legs by 6%-11% at Post24 (p < 0.05). In conclusion, both short-term high-frequency failure and non-failure BFRRE induced increases in SCs, in myonuclei content, muscle size, and strength, concomitant with decreased echo intensity. Intriguingly, the responses were delayed and peaked 10-24 days after the training intervention. Our findings may shed light on the mechanisms involved in resistance exercise-induced overreaching and supercompensation.

Should we individualize training based on force-velocity profiling to improve physical performance in athletes?

The present study aimed to examine the effectiveness of an individualized training program based on force-velocity (FV) profiling on jumping, sprinting, strength, and power in athletes. Forty national level team sport athletes (20 ± 4years, 83 ± 13 kg) from ice-hockey, handball, and soccer completed a 10-week training intervention. A theoretical optimal squat jump (SJ)-FV-profile was calculated from SJ with five different loads (0, 20, 40, 60, and 80 kg). Based on their initial FV-profile, athletes were randomized to train toward, away, or irrespective (balanced training) of their initial theoretical optimal FV-profile. The training content was matched between groups in terms of set x repetitions but varied in relative loading to target the different aspects of the FV-profile. The athletes performed 10 and 30 m sprints, SJ and countermovement jump (CMJ), 1 repetition maximum (1RM) squat, and a leg-press power test before and after the intervention. There were no significant group differences for any of the performance measures. Trivial to small changes in 1RM squat (2.9%, 4.6%, and 6.5%), 10 m sprint time (1.0%, -0.9%, and -1.7%), 30 m sprint time (0.9%, -0.6%, and -0.4%), CMJ height (4.3%, 3.1%, and 5.7%), SJ height (4.8%, 3.7%, and 5.7%), and leg-press power (6.7%, 4.2%, and 2.9%) were observed in the groups training toward, away, or irrespective of their initial theoretical optimal FV-profile, respectively. Changes toward the optimal SJ-FV-profile were negatively correlated with changes in SJ height (r = -0.49, p < 0.001). Changes in SJ-power were positively related to changes in SJ-height (r = 0.88, p < 0.001) and CMJ-height (r = 0.32, p = 0.044), but unrelated to changes in 10 m (r = -0.02, p = 0.921) and 30 m sprint time (r = -0.01, p = 0.974). The results from this study do not support the efficacy of individualized training based on SJ-FV profiling.

Does exercise intensity matter for fatigue during (neo-)adjuvant cancer treatment? The Phys-Can randomized clinical trial.

Exercise during cancer treatment improves cancer-related fatigue (CRF), but the importance of exercise intensity for CRF is unclear. We compared the effects of high- vs low-to-moderate-intensity exercise with or without additional behavior change support (BCS) on CRF in patients undergoing (neo-)adjuvant cancer treatment. This was a multicenter, 2x2 factorial design randomized controlled trial (Clinical Trials NCT02473003) in Sweden. Participants recently diagnosed with breast (n = 457), prostate (n = 97) or colorectal (n = 23) cancer undergoing (neo-)adjuvant treatment were randomized to high intensity (n = 144), low-to-moderate intensity (n = 144), high intensity with BCS (n = 144) or low-to-moderate intensity with BCS (n = 145). The 6-month exercise intervention included supervised resistance training and home-based endurance training. CRF was assessed by Multidimensional Fatigue Inventory (MFI, five subscales score range 4-20), and Functional Assessment of Chronic Illness Therapy-Fatigue scale (FACIT-F, score range 0-52). Multiple linear regression for main factorial effects was performed according to intention-to-treat, with post-intervention CRF as primary endpoint. Overall, 577 participants (mean age 58.7 years) were randomized. Participants randomized to high- vs low-to-moderate-intensity exercise had lower physical fatigue (MFI Physical Fatigue subscale; mean difference -1.05 [95% CI: -1.85, -0.25]), but the difference was not clinically important (ie <2). We found no differences in other CRF dimensions and no effect of additional BCS. There were few minor adverse events. For CRF, patients undergoing (neo-)adjuvant treatment for breast, prostate or colorectal cancer can safely exercise at high- or low-to-moderate intensity, according to their own preferences. Additional BCS does not provide extra benefit for CRF in supervised, well-controlled exercise interventions.

Effects of a school-based physical activity intervention on academic performance in 14-year old adolescents: a cluster randomized controlled trial - the School in Motion study.

BACKGROUND: School-based physical activity interventions evaluating the effect on academic performance usually includes children. We aimed to investigate the effect of a nine-month, school-based physical activity intervention titled School in Motion (ScIM) on academic performance in adolescents. METHODS: Thirty secondary schools in Norway were cluster-randomized into three groups: the Physically active learning (PAL) group (n = 10), the Don't worry - Be Happy (DWBH) group (n = 10) or control (n = 10). Target dose in both intervention groups was 120 min/week of additional PA during school hours. Parental consent was obtained from 2084 adolescent students (76%). Standardized national tests in reading and numeracy was conducted at baseline and at the end of the intervention. We used linear mixed model to test intervention effects. We found significant intervention effects in numeracy and reading among students in both interventions when compared with controls. RESULTS: The mean difference in change in numeracy was 1.7 (95% CI: 0.9 to 2.5; Cohen's d = 0.12) and 2.0 (95% CI: 1.4 to 2.7; Cohen's d = 0.23) points in favour of students in the PAL and DWBH intervention, respectively. Similar results were found for reading, where the mean difference in change was 0.9 (95% CI 0.2 to 1.6; Cohen's d = 0.06) and 1.1 (95% CI 0.3 to 1.9; Cohen's d = 0.18) points in favour of students in the PAL and DWBH intervention, respectively. When conducting intention to treat analysis with imputed data the estimates were attenuated and some no longer significant. CONCLUSION: The ScIM study demonstrates that two different school-based PA interventions providing approximately 120 min of additional PA weekly over nine months, significantly improved numeracy and reading performance in 14-year old students compared with controls. However, the results should be interpreted with caution as the effect sizes reported were very small or small and the estimates were attenuated when conducting intention to treat analysis. Despite this, our results are still positive and suggest that PA interventions are viable models to increase academic performance among adolescents. TRIAL REGISTRATION: Retrospectively registered (25/01/2019): NCT03817047 .

Deep Learning for Classifying Physical Activities from Accelerometer Data.

Physical inactivity increases the risk of many adverse health conditions, including the world's major non-communicable diseases, such as coronary heart disease, type 2 diabetes, and breast and colon cancers, shortening life expectancy. There are minimal medical care and personal trainers' methods to monitor a patient's actual physical activity types. To improve activity monitoring, we propose an artificial-intelligence-based approach to classify physical movement activity patterns. In more detail, we employ two deep learning (DL) methods, namely a deep feed-forward neural network (DNN) and a deep recurrent neural network (RNN) for this purpose. We evaluate the two models on two physical movement datasets collected from several volunteers who carried tri-axial accelerometer sensors. The first dataset is from the UCI machine learning repository, which contains 14 different activities-of-daily-life (ADL) and is collected from 16 volunteers who carried a single wrist-worn tri-axial accelerometer. The second dataset includes ten other ADLs and is gathered from eight volunteers who placed the sensors on their hips. Our experiment results show that the RNN model provides accurate performance compared to the state-of-the-art methods in classifying the fundamental movement patterns with an overall accuracy of 84.89% and an overall F1-score of 82.56%. The results indicate that our method provides the medical doctors and trainers a promising way to track and understand a patient's physical activities precisely for better treatment.