Reductions of cardiovascular and metabolic risk factors after a 14-week periodized training model in patients with knee osteoarthritis: a randomized controlled trial.

INTRODUCTION/OBJECTIVE: To evaluate the effects of a periodized circuit training (CT) compared with a conventional strength training (ST) and an educational protocol (EP) on body composition, metabolic parameters, muscle strength, pain, and physical performance in patients with knee osteoarthritis (KOA). METHOD: This study followed a randomized controlled trial design. A sample of sixty-one patients with KOA, 40-65 years old and BMI < 30 kg/m2, were randomly divided into three 14-week protocols: CT, ST, or EP. The CT performed whole body exercises organized in circuit, 3 times a week. The ST performed conventional resistance exercises also 3 times a week, and the EP joined in educational meetings twice a month. Body composition (dual-energy X-ray absorptiometry (DXA)); metabolic parameters (abdominal obesity, triglyceride, HDL, blood pressure and fasting glucose), knee maximal isometric voluntary contraction (MIVC) extension and flexion, performance-based tests (40-m walk test, 30-s chair test, and stair climb test), self-reported pain, stiffness, and physical function (WOMAC) and pain catastrophism were evaluated at baseline and follow-up. Repeated measures ANOVA were used to compare differences between groups (CTxSTxEP) at the different times of assessment (baseline × follow-up). When group-time interaction was found, a one-way ANOVA, followed by a Bonferroni post hoc test, was used to compare groups in each time point; while a paired t test was used to verify the time effect in each group. Additionally, the training effect was analyzed in terms of the percent change (Δ%). Effect size was calculated for post intervention (week 14) between groups. For all analyses a significance level of 5% was adopted (p < 0.05). RESULTS: The CT was the only protocol that presented significant lower body mass (p = 0.018; Δ% = - 1.4), fat mass (p = 0.017; Δ% = - 10.3), %fat mass (p < 0.001; Δ% = - 13.9), adipose indices (%fat trunk/%fat legs p = 0.031; Δ% = 7.8; fat mass/height2 p = 0.011; Δ% = - 15.1; trunk/limb fat mass p = 0.012; Δ% = - 8.2; visceral adipose tissue (VAT) volume (cm3) p = 0.039; Δ% = - 11.6; VAT area (cm2) p = 0.044; Δ% = - 12.2), blood pressure levels (SBP p = 0.042; Δ% = - 3.4 and DBP p = 0.001; Δ% = - 4.9), higher lean mass and HDL (p < 0.001; Δ% = 5.9) compared to baseline. CT and ST presented lower WOMAC pain, stiffness and physical function (p < 0.001; Δ% = - 64.0 for CT and p < 0.001; Δ% = 0.001; Δ% = - 46.4 for ST in WOMAC total score, pain catastrophizing (p < 0.001; Δ% = - 66.7 for CT and p < 0.001; Δ% = - 61.5 for ST) a higher functional performance (30 s chair test: p < 0.001; Δ% = 45.7 for CT and p < 0.001; Δ% = 26.9 for ST; 40 m walk test: p < 0.001; Δ% = 26.7 for CT and p < 0.001; Δ% = 12.5 for ST; stair climb test: p = 0.002; Δ% = - 33.9 for CT and p < 0.001; Δ% = - 18.8 for ST) and knee extension MIVC (p < 0.001; Δ% = 21.92 for CT and p < 0.001; Δ% = 30.25 for ST). CONCLUSION: A periodized CT model reduces visceral adipose tissue, SBP and DBP, and improves HDL, important cardiovascular and metabolic risk factors, in patients with KOA. Both trained groups (CT and ST) improve self-reported clinical symptoms, muscle strength, and physical performance in this sample. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov , NCT02761590 (registered on May 4, 2016). KEY POINTS: • A 14-week periodized circuit training reduces visceral adipose tissue, systolic and diastolic blood pressure, and improves HDL blood levels in patients with knee osteoarthritis. • Both periodized circuit training and conventional strength training improve clinical symptoms, functional performance and muscle strength in this sample.

A periodized training attenuates thigh intermuscular fat and improves muscle quality in patients with knee osteoarthritis: results from a randomized controlled trial.

OBJECTIVE: To analyze the influence of a 14-week periodized circuit training (CT) protocol on thigh intermuscular fat and muscle quality (force per unit area of lean tissue) in patients with knee osteoarthritis (KOA). DESIGN: Randomized controlled trial METHODS: Sixty-one selected participants with KOA grades 2 and 3, 40-65 years old, and BMI < 30 kg/m2 were randomized into three groups: CT, conventional strength training (ST), and educational protocol (EP). The CT and ST protocols consisted of 14-week training protocols conducted 3 times a week. The CT group performed exercises stratified as light, moderate, and intense, arranged progressively in a circuit model. The ST group performed conventional strength exercises, and the EP group participated in lectures twice a month about healthy lifestyles. Baseline and follow-up (week 0 and week 14) evaluations were conducted for thigh intermuscular fat (computed tomography), knee extension maximal isometric voluntary contraction (MIVC), and muscle quality (knee extension MIVC/muscle mass cross-sectional area). RESULTS: Only the CT group presented significant reductions in thigh intermuscular fat (p = 0.003) and significantly lower values in week 14 compared with the EP (p = 0.032). Both trained groups presented significant increases in muscle mass area (p=0.002 for CT and p=0.008 for ST) and increments in knee extension MIVC (p=0,033 for CT nd p=0.019 for ST) in week 14 compared with the EP and increases in muscle quality (p = 0.004 and 0.042). CONCLUSION: It can be concluded that a 14-week periodized CT protocol attenuates thigh intermuscular fat and improves muscle quality in patients with KOA. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02761590; https://clinicaltrials.gov/ct2/show/NCT02761590Key Points•Fourteen weeks of periodized circuit training attenuates thigh intermuscular fat in patients with knee osteoarthritis.•Circuit training is as effective as strength training for improving muscle mass, strength, and quality.

Evaluation of vastus lateralis architecture and strength of knee extensors in middle-aged and older individuals with knee osteoarthritis.

OBJECTIVES: To investigate any differences in muscle architecture (fascicle angle, fascicle length, and muscle thickness) and muscle strength in people of different ages with and without knee osteoarthritis (OA). METHODS: This is a cross-sectional study conducted with 40 individuals with and 40 without knee OA. Four groups were analyzed, middle-aged OA group (KL II/III) aged 40-50 years (n = 20), middle-aged healthy (H) group aged 40-50 years (n = 20), older OA group (KL II/III) aged 70 years and over (n = 20), and older H group, aged 70 years and over (n = 20). Outcomes analyzed were isometric and isokinetic peak torque of knee extensors, level of physical activity, self-reported pain level, and vastus lateralis fascicle length, fascicle angle, and muscle thickness assessed by ultrasound. One-way ANOVA was used to identify differences between groups, followed by the Tukey post hoc test. RESULTS: There were no differences between the middle-aged OA group and older H group for any variables. The older OA group presented the smallest muscle architecture parameters and worst isometric and concentric peak torques compared to the other three groups (p < 0.001). In contrast, the middle-aged H group presented the largest muscle architecture parameters and was the strongest group compared to the others (p < 0.001). CONCLUSIONS: The presence of knee OA is associated with early muscular changes and seems to intensify these thigh changes that are similar to the effects of the aging process.

Fatty infiltration in the thigh muscles in knee osteoarthritis: a systematic review and meta-analysis.

Knee osteoarthritis is a chronic degenerative joint disease, influenced by inflammatory, mechanical and metabolic processes. Current literature shows that thigh muscles of people with knee osteoarthritis can have increased infiltration of fat, both between and within the muscles (inter- and intramuscular fat). The fatty infiltration in the thigh in this population is correlated to systemic inflammation, poor physical function, and muscle impairment and leads to metabolic impairments and muscle disfunction. The objective of this study is to systematically review the literature comparing the amount of fatty infiltration between people with knee osteoarthritis and healthy controls. A literature search on the databases MEDLINE, Embase, CINAHL SPORTDiscuss, Web of Science and Scopus from insertion to December 2018, resulted in 1035 articles, from which 7 met inclusion/exclusion criteria and were included in the review. All included studies analyzed the difference in intermuscular fat and only one study analyzed intramuscular fat. A meta-analysis (random effects model) transforming data into standardized mean difference was performed for intermuscular fat (six studies). The meta-analysis showed a standardized mean difference of 0.39 (95% confidence interval from 0.25 to 0.53), showing that people with knee osteoarthritis have more intermuscular fat than healthy controls. The single study analyzing intramuscular fat shows that people with knee osteoarthritis have more intramuscular fat fraction than healthy controls. People with knee osteoarthritis have more fatty infiltration around the thigh than people with no knee osteoarthritis. That conclusion is stronger for intermuscular fat than intramuscular fat, based on the quality and number of studies analyzed.

Influence of a periodized circuit training protocol on intermuscular adipose tissue of patients with knee osteoarthritis: protocol for a randomized controlled trial.

BACKGROUND: The objective of this study is to analyze the influence of a 14-week periodized circuit training protocol on patients with knee osteoarthritis (OA), in randomized intervention groups, on thigh intermuscular adipose tissue (interMAT), body composition, systemic inflammation, cartilage degradation, and its repercussion on pain, functional performance and quality of life. METHODS: This study presents a protocol for a randomized controlled trial. Sixty selected participants diagnosed with knee OA grades II and III, 40-65 years old and BMI < 30 kg/m2, will be randomly divided into three groups:periodized circuit training, strength training, and educational protocol. The circuit training and strength training protocols consist of 14-week training protocols conducted 3 times a week. The circuit training group will perform selected exercises previously stratified as light, moderate, and intense, arranged progressively in a circuit model, the strength group will perform regular strength exercises, and the educational protocol group will participate in a 14-week protocol with lectures twice a month about healthy lifestyles. Baseline and follow-up evaluations will be conducted for thigh interMAT (computed tomography), body composition (DXA), inflammation (IL-1ß, IL-6, IL-10, TNF-α, leptin, and adiponectin), and joint degradation biomarkers (uCTX-II and sCOMP), performance-based tests (30s Chair Stand Test, 40 m Fast-paced Walk Test and Stair Climb Test), quadriceps and hamstring maximal isometric voluntary contraction (MIVC), and questionnaires (WOMAC and pain catastrophizing scale). Repeated measures ANOVA will be used to compare differences between groups (circuit training X strength training X educational protocol) at the different times of assessment (baseline x follow-up or baseline x during protocol x follow-up) for each of the dependent variables. When significant main effects were found, the pots hoc Bonferroni test will be used to identify statistical differences. A significance level of 5% (p < 0.05) will be adopted. DISCUSSION: This will be the first randomized controlled trial to assess the effects of a circuit training protocol on patients with knee OA on thigh intermuscular adipose tissue (interMAT). Given the prevalence and impact of OA and the widespread availability of this intervention, assessing the efficacy of a low-cost, non-pharmacological, and non-invasive treatment for knee OA patients has the potential for immediate and high clinical impact. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02761590 , registered in May 4, 2016.