Ulrik Dalgas

Fatigue, mood and quality of life improve in MS patients after progressive resistance training

Fatigue occurs in the majority of multiple sclerosis patients and therapeutic possibilities are few. Fatigue, mood and quality of life were studied in patients with multiple sclerosis following progressive resistance training leading to improvement of muscular strength and functional capacity. Fatigue (Fatigue Severity Scale, FSS), mood (Major Depression Inventory, MDI) and quality of life (physical and mental component scores, PCS and MCS, of SF36) were scored at start, end and follow-up of a randomized controlled clinical trial of 12 weeks of progressive resistance training in moderately disabled (Expanded Disability Status Scale, EDSS: 3—5.5) multiple sclerosis patients including a Control group (n = 15) and an Exercise group (n = 16). Fatigue (FSS > 4) was present in all patients. Scores of FSS, MDI, PCS—SF36 and MCS—SF36 were comparable at start of study in the two groups. Fatigue improved during exercise by —0.6 (95% confidence interval (CI) —1.4 to 0.4) a.u. vs. 0.1 (95% CI —0.4 to 0.6) a.u. in controls (p = 0.04), mood improved by —2.4 (95% CI —4.1 to 0.7) a.u. vs. 1.1 (—1.2 to 3.4) a.u. in controls (p = 0.01) and quality of life (PCS—SF36) improved by 3.5 (95% CI 1.4—5.7) a.u. vs. —1.0 (95% CI —3.4—1.4) a.u. in controls (p = 0.01). The beneficial effect of progressive resistance training on all scores was maintained at follow-up after further 12 weeks. Fatigue, mood and quality of life all improved following progressive resistance training, the beneficial effect being maintained for at least 12 weeks after end of intervention.

The effect of exercise therapy on fatigue in multiple sclerosis

Background: Fatigue occurs in the majority of patients with multiple sclerosis (MS) and therapeutic possibilities are few. Exercise therapy is a therapeutic option but no studies have systematically reviewed the existing literature evaluating the effect of exercise therapy on MS fatigue. Objective: To determine the effect of exercise therapy on MS fatigue by systematically reviewing the literature. Methods: A comprehensive literature search (PubMed, SweMed +, Embase, Cochrane, CINAHL, PEDro, Sport Discuss and Bibliotek.dk) was conducted. Results: Studies evaluating the effect of exercise therapy on MS fatigue show heterogeneous results and only few studies have evaluated MS fatigue as the primary outcome. The heterogeneous findings seem to be related to the selected study population, which in many studies are non-fatigued. Most studies that have included fatigued patients with MS show positive effects, although it is not clear whether any exercise modalities are superior to others because there are no comparative studies regarding different exercise interventions. Conclusion: Exercise therapy has the potential to induce a positive effect on MS fatigue, but findings are heterogeneous probably because many studies have applied non-fatigued study populations. Furthermore, only few studies have evaluated MS fatigue as the primary outcome measure, emphasizing the need for future studies within this field.

Multiple sclerosis and progressive resistance training: a systematic review

Recently progressive resistance training (PRT) has been recognised as an effective tool in the rehabilitation of persons with multiple sclerosis (MS). The objective of this study was to systematically review the literature of PRT studies for persons with MS. A comprehensive literature search (PubMed, SveMed+, Embase, Cochrane, PEDro, SPORTDiscus and Bibliotek.dk) was conducted. Identified papers were rated according to the PEDro-scale. Sixteen studies were included and scored between 3 and 8 of 11 total points on the PEDro-scale, showing a general lack of blinding. Strong evidence regarding the beneficial effect of PRT on muscle strength was observed. Regarding functional capacity, balance and self-reported measures (fatigue, quality of life and mood) evidence is less strong, but the tendency is overall positive. Indications of an effect on underlying mechanisms such as muscle morphological changes, neural adaptations and cytokines also exist, but the studies investigating these aspects are few and inconclusive. PRT has a positive effect on muscle strength for persons with MS. Heterogeneous results exist regarding the effect on functional capacity and self-reported measures probably because of differences in training protocols, samples sizes, type and severity of MS. The area of underlying mechanisms deserves more attention in future research.

Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients.

Although the negative effects of bed rest on muscle strength and muscle mass are well established, it still remains a challenge to identify effective methods to restore physical capacity of elderly patients recovering from hospitalization. The present study compared different training regimes with respect to muscle strength, muscle fiber size, muscle architecture, and stair walking power in elderly postoperative patients. Thirty-six patients (60-86 yr) scheduled for unilateral hip replacement surgery due to hip osteoarthritis were randomized to either 1) resistance training (RT: 3/wk x 12 wk), 2) electrical stimulation (ES: 1 h/day x 12 wk), or 3) standard rehabilitation (SR: 1 h/day x 12 wk). All measurements were performed at baseline, at 5 wk and 12 wk postsurgery. After 12 wk of resistance training, maximal dynamic muscle strength increased by 30% at 60 degrees /s (P < 0.05) and by 29% at 180 degrees /s (P < 0.05); muscle fiber area increased for type I (+17%, P < 0.05), type IIa (+37%, P < 0.05), and type IIx muscle fibers (+51%, P < 0.05); and muscle fiber pennation angle increased by 22% and muscle thickness increased by 15% (P < 0.05). Furthermore, stair walking power increased by 35% (P < 0.05) and was related to the increase in type II fiber area (r = 0.729, P < 0.05). In contrast, there was no increase in any measurement outcomes with electrical stimulation and standard rehabilitation. The present study is the first to demonstrate the effectiveness of resistance training to induce beneficial qualitative changes in muscle fiber morphology and muscle architecture in elderly postoperative patients. In contrast, rehabilitation regimes based on functional exercises and neuromuscular electrical stimulation had no effect. The present data emphasize the importance of resistance training in future rehabilitation programs for elderly individuals.

Exercise and disease progression in multiple sclerosis: can exercise slow down the progression of multiple sclerosis?

It has been suggested that exercise (or physical activity) might have the potential to have an impact on multiple sclerosis (MS) pathology and thereby slow down the disease process in MS patients. The objective of this literature review was to identify the literature linking physical exercise (or activity) and MS disease progression. A systematic literature search was conducted in the following databases: PubMed, SweMed+, Embase, Cochrane Library, PEDro, SPORTDiscus and ISI Web of Science. Different methodological approaches to the problem have been applied including (1) longitudinal exercise studies evaluating the effects on clinical outcome measures, (2) cross-sectional studies evaluating the relationship between fitness status and MRI findings, (3) cross-sectional and longitudinal studies evaluating the relationship between exercise/physical activity and disability/relapse rate and, finally, (4) longitudinal exercise studies applying the experimental autoimmune encephalomyelitis (EAE) animal model of MS. Data from intervention studies evaluating disease progression by clinical measures (1) do not support a disease-modifying effect of exercise; however, MRI data (2), patient-reported data (3) and data from the EAE model (4) indicate a possible disease-modifying effect of exercise, but the strength of the evidence limits definite conclusions. It was concluded that some evidence supports the possibility of a disease-modifying potential of exercise (or physical activity) in MS patients, but future studies using better methodologies are needed to confirm this.

Effects of sprint interval training on VO2max and aerobic exercise performance: A systematic review and meta-analysis

Recently, several studies have examined whether low‐volume sprint interval training (SIT) may improve aerobic and metabolic function. The objective of this study was to systematically review the existing literature regarding the aerobic and metabolic effects of SIT in healthy sedentary or recreationally active adults. A systematic literature search was performed (Bibliotek.dk, SPORTDiscus, Embase, PEDro, SveMed+, and Pubmed). Meta‐analytical procedures were applied evaluating effects on maximal oxygen consumption (VO2max). Nineteen unique studies [four randomized controlled trials (RCTs), nine matched‐controlled trials and six noncontrolled studies] were identified, evaluating SIT interventions lasting 2–8 weeks. Strong evidence support improvements of aerobic exercise performance and VO2max following SIT. A meta‐analysis across 13 studies evaluating effects of SIT on VO2max showed a weighted mean effects size of g = 0.63 95% CI (0.39; 0.87) and VO2max increases of 4.2–13.4%. Solid evidence support peripheral adaptations known to increase the oxidative potential of the muscle following SIT, whereas evidence regarding central adaptations was limited and equivocal. Some evidence indicated changes in substrate oxidation at rest and during exercise as well as improved glycemic control and insulin sensitivity following SIT. In conclusion, strong evidence support improvement of aerobic exercise performance and VO2max following SIT, which coincides with peripheral muscular adaptations. Future RCTs on long‐term SIT and underlying mechanisms are warranted.

Responsiveness and Clinically Meaningful Improvement, According to Disability Level, of Five Walking Measures After Rehabilitation in Multiple Sclerosis A European Multicenter Study

Background. Evaluation of treatment effects on walking requires appropriate and responsive outcome measures. Objectives. To determine responsiveness of 5 walking measures and provide reference values for clinically meaningful improvements, according to disability level, in persons with multiple sclerosis (pwMS). Methods. Walking tests were measured pre- and postrehabilitation in 290 pwMS from 17 European centers. Combined anchor- and distribution-based methods determined responsiveness of objective short and long walking capacity tests (Timed 25-Foot Walk [T25FW] and 2- and 6-Minute Walk Tests [2MWT and 6MWT] and of the patient-reported Multiple Sclerosis Walking Scale–12 [MSWS-12]). A global rating of change scale, from patients’ and therapists’ perspective, was used as external criteria to determine the area under the receiver operating characteristic curve (AUC), minimally important change (MIC), and smallest real change (SRC). Patients were stratified into disability subgroups (Expanded Disability Status Scale score ≤4 [n = 98], >4 [n = 186]). Results. MSWS-12, 2MWT, and 6MWT were more responsive (AUC 0.64-0.73) than T25FW (0.50-0.63), especially in moderate to severely disabled pwMS. Clinically meaningful changes (MICs) from patient and therapist perspective were −10.4 and −11.4 for MSWS-12 (P < .01), 9.6 m and 6.8 m for 2MWT (P < .05), and 21.6 m (P < .05) and 9.1 m (P = .3) for 6MWT. In subgroups, MIC was significant from patient perspective for 2MWT (10.8 m) and from therapist perspective for MSWS-12 (−10.7) in mildly disabled pwMS. In moderate to severely disabled pwMS, MIC was significant for MSWS-12 (−14.1 and −11.9). Conclusions. Long walking tests and patient-reported MSWS-12 were more appropriate than short walking tests in detecting clinically meaningful improvement after physical rehabilitation, particularly the MSWS-12 for moderate to severely disabled pwMS.

Risk factors related to cardiovascular diseases and the metabolic syndrome in multiple sclerosis – a systematic review

Despite many epidemiological studies examining comorbidity in people with multiple sclerosis (pMS), there are conflicting opinions on whether pMS are at more or less risk of cardiovascular disease (CVD) and the metabolic syndrome compared with the general population. As pMS can now expect longer survival, this as an important question both at an individual and public health level. This study aimed to systematically review the literature linking MS to CVD risks and to the risk factors constituting the metabolic syndrome. This systematic review is based on a comprehensive literature search of six databases (Swemed+, Pubmed, Embase, Cochrane, PEDro and CINAHL). In total 34 studies were identified. Despite the high number of identified papers, only limited and inconsistent data exist on the risk factors of the metabolic syndrome and MS. Overall, the data suggest an increased CVD risk in pMS. From the existing studies it is not clear whether the increased risk of CVD is related to an increased risk of obesity or changes in body composition, hypertension, dyslipidemia or type II diabetes in pMS, indicating the need for future research in the field, if we are to advise pMS adequately in avoiding preventable comorbidity.

Muscle fiber size increases following resistance training in multiple sclerosis.

Objective: To test the hypothesis that lower body progressive resistance training (PRT) leads to an increase of the muscle fiber cross-sectional area (CSA) and a shift in the proportion of fiber types in patients with multiple sclerosis (MS). Methods: The present study was a two-arm, randomized controlled trial (RCT). Thirty-eight MS patients (Expanded Disability Status Scale (EDSS) 3—5.5) were randomized to a PRT group (Exercise, n = 19) or a control group (Control, n = 19). The Exercise group performed a biweekly 12-week lower body PRT program [five exercises progressing from 15RM (Repetition Maximum) towards 8RM], whereas the Control group maintained their usual daily activity level during the trial period. Muscle biopsies from vastus lateralis were taken before (pre) and after the trial (post). Thigh volume (TV) was estimated from anthropometric measurements. Isokinetic muscle strength of the knee extensors (KE) and flexors (KF) were evaluated at slow (90°/s) and fast (180°/s) angular velocities. Results: In the Exercise group the mean CSA of all muscle fibers (7.9 ± 15.4% vs. -3.5 ± 9.0%, p = 0.03) and of type II muscle fibers (14.0 ± 19.4% vs. -2.6 ± 15.5%, p = 0.02) increased in comparison with the Control group. No changes occurred in the proportion of fiber types in the Exercise group. Neither was there any change in total TV. Isokinetic strength at KE180, KF90 and KF180 improved significantly after PRT when compared with the control group (10.2—21.3%, p ≤ 0.02). Conclusions: We conclude that progressive resistance training induces a compensatory increase of muscle fiber size in patients with the central nervous system disorder, multiple sclerosis.

Muscle morphological and strength adaptations to endurance vs. resistance training

Farup, J, Kjølhede, T, Sørensen, H, Dalgas, U, Møller, AB, Vestergaard, PF, Ringgaard, S, Bojsen-Møller, J, and Vissing, K. Muscle morphological and strength adaptations to endurance vs. resistance training. J Strength Cond Res 26(2): 398–407, 2012—Fascicle angle (FA) is suggested to increase as a result of fiber hypertrophy and furthermore to serve as the explanatory link in the discrepancy in the relative adaptations in the anatomical cross-sectional area (CSA) and fiber CSA after resistance training (RT). In contrast to RT, the effects of endurance training on FA are unclear. The purpose of this study was therefore to investigate and compare the longitudinal effects of either progressive endurance training (END, n = 7) or RT (n = 7) in young untrained men on FA, anatomical CSA, and fiber CSA. Muscle morphological measures included the assessment of vastus lateralis FA obtained by ultrasonography and anatomical CSA by magnetic resonance imaging of the thigh and fiber CSA deduced from histochemical analyses of biopsy samples from m. vastus lateralis. Functional performance measures included &OV0312;;O2max and maximal voluntary contraction (MVC). The RT produced increases in FA by 23 ± 8% (p < 0.01), anatomical CSA of the knee extensor muscles by 9 ± 3% (p = 0.001), and fiber CSA by 19 ± 7% (p < 0.05). RT increased knee extensor MVC by 20 ± 5% (p < 0.001). END increased &OV0312;;O2max by 10 ± 2% but did not evoke changes in FA, anatomical CSA, or in fiber CSA. In conclusion, the morphological changes induced by 10 weeks of RT support that FA does indeed serve as the explanatory link in the observed discrepancy between the changes in anatomical and fiber CSA. Contrarily, 10 weeks of endurance training did not induce changes in FA, but the lack of morphological changes from END indirectly support the fact that fiber hypertrophy and FA are interrelated.