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- Strandberg, Emelie, et al.
(author)
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Effects of heavy-load resistance training during (neo-)adjuvant chemotherapy on muscle cellular outcomes in women with breast cancer
- 2021
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In: Medicine. - 0025-7974 .- 1536-5964. ; 100:10
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Journal article (peer-reviewed)abstract
- Introduction: (Neo-)adjuvant chemotherapy for breast cancer has a deleterious impact on muscle tissue resulting in reduced cardiorespiratory fitness, skeletal muscle mass and function. Physical exercise during treatment may counteract some of these negative effects. However, the effects of resistance training (RT) alone have never been explored. The present study aims to investigate if heavy-load RT during (neo-)adjuvant chemotherapy counteracts deleterious effects on skeletal muscle in women diagnosed with breast cancer. We hypothesize that (neo-)adjuvant treatment with chemotherapy will reduce muscle fiber size, impair mitochondrial function, and increase indicators of cellular stress and that RT during treatment will counteract these negative effects. We also hypothesize that RT during (neo-)adjuvant chemotherapy will increase muscle and blood levels of potential antitumor myokines and reduce treatment-related side effects on muscle strength and cardiorespiratory fitness.Methods: Fifty women recently diagnosed with breast cancer scheduled to start (neo-)adjuvant chemotherapy will be randomized to either randomized to either intervention group or to control group.The intervention group will perform supervised heavy-load RT twice a week over the course of chemotherapy (approximately 16-weeks) whereas the control group will be encouraged to continue with their usual activities. Muscle biopsies from m. vastus lateralis will be collected before the first cycle of chemotherapy (T0), after chemotherapy (T1), and 6 months later (T2) for assessment of muscle cellular outcomes. The primary outcome for this study is muscle fiber size. Secondary outcomes are: regulators of muscle fiber size and function, indicators of cellular stress and mitochondrial function, myokines with potential antitumor effects, muscle strength, and cardiorespiratory fitness.Ethics and dissemination: Ethical approval has been obtained from the Regional Ethical Review Board in Uppsala, Sweden (Dnr:2016/230/2). Results will be disseminated through presentations at scientific meetings, publications in peer-reviewed journals, social media, and patient organizations.Trial registration number: NCT04586517.
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| 3. |
- Vikmoen, Olav, et al.
(author)
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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
- 2024
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In: The FASEB Journal. - : John Wiley & Sons. - 0892-6638 .- 1530-6860. ; 38:13
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Journal article (peer-reviewed)abstract
- 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.
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