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result(s) for
"Levinger, Itamar"
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Progressive Resistance Training for Concomitant Increases in Muscle Strength and Bone Mineral Density in Older Adults: A Systematic Review and Meta-Analysis
by
Smith, Cassandra
,
O’Bryan, Steven J.
,
Woessner, Mary N.
in
Aged
,
Bone density
,
Bone Density - physiology
2022
Background
Older adults experience considerable muscle and bone loss that are closely interconnected. The efficacy of progressive resistance training programs to concurrently reverse/slow the age-related decline in muscle strength and bone mineral density (BMD) in older adults remains unclear.
Objectives
We aimed to quantify concomitant changes in lower-body muscle strength and BMD in older adults following a progressive resistance training program and to determine how these changes are influenced by mode (resistance only vs. combined resistance and weight-bearing exercises), frequency, volume, load, and program length.
Methods
MEDLINE/PubMed and Embase databases were searched for articles published in English before 1 June, 2021. Randomized controlled trials reporting changes in leg press or knee extension one repetition maximum and femur/hip or lumbar spine BMD following progressive resistance training in men and/or women ≥ 65 years of age were included. A random-effects meta-analysis and meta-regression determined the effects of resistance training and the individual training characteristics on the percent change (∆%) in muscle strength (standardized mean difference) and BMD (mean difference). The quality of the evidence was assessed using the Cochrane risk-of-bias tool (version 2.0) and Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) criteria.
Results
Seven hundred and eighty studies were identified and 14 were included. Progressive resistance training increased muscle strength (∆ standardized mean difference = 1.1%; 95% confidence interval 0.73, 1.47;
p
≤ 0.001) and femur/hip BMD (∆ mean difference = 2.77%; 95% confidence interval 0.44, 5.10;
p
= 0.02), but not BMD of the lumbar spine (∆ mean difference = 1.60%; 95% confidence interval − 1.44, 4.63;
p
= 0.30). The certainty for improvement was greater for muscle strength compared with BMD, evidenced by less heterogeneity (
I
2
= 78.1% vs 98.6%) and a higher overall quality of evidence. No training characteristic significantly affected both outcomes (
p
> 0.05), although concomitant increases in strength and BMD were favored by higher training frequencies, increases in strength were favored by resistance only and higher volumes, and increases in BMD were favored by combined resistance plus weight-bearing exercises, lower volumes, and higher loads.
Conclusions
Progressive resistance training programs concomitantly increase lower-limb muscle strength and femur/hip bone mineral density in older adults, with greater certainty for strength improvement. Thus, to maximize the efficacy of progressive resistance training programs to concurrently prevent muscle and bone loss in older adults, it is recommended to incorporate training characteristics more likely to improve BMD.
Journal Article
Undercarboxylated Osteocalcin: Experimental and Human Evidence for a Role in Glucose Homeostasis and Muscle Regulation of Insulin Sensitivity
2018
Recent advances have indicated that osteocalcin, and in particular its undercarboxylated form (ucOC), is not only a nutritional biomarker reflective of vitamin K status and an indicator of bone health but also an active hormone that mediates glucose metabolism in experimental studies. This work has been supported by the putative identification of G protein-coupled receptor, class C, group 6, member A (GPRC6A) as a cell surface receptor for ucOC. Of note, ucOC has been associated with diabetes and with cardiovascular risk in epidemiological studies, consistent with a pathophysiological role for ucOC in vivo. Limitations of existing knowledge include uncertainty regarding the underlying mechanisms by which ucOC interacts with GPRC6A to modulate metabolic and cardiovascular outcomes, technical issues with commonly used assays for ucOC in serum, and a paucity of clinical trials to prove causation and illuminate the scope for novel health interventions. A key emerging area of research is the role of ucOC in relation to expression of GPRC6A in muscle, and whether exercise interventions may modulate metabolic outcomes favorably in part via ucOC. Further research is warranted to clarify potential direct and indirect roles for ucOC in human health and cardiometabolic diseases.
Journal Article
The Effects of Exercise Training in Addition to Energy Restriction on Functional Capacities and Body Composition in Obese Adults during Weight Loss: A Systematic Review
by
Miller, Clint T.
,
Straznicky, Nora E.
,
Selig, Steve E.
in
Activities of daily living
,
Adult
,
Adults
2013
Obesity is associated with impairments of physical function, cardiovascular fitness, muscle strength and the capacity to perform activities of daily living. This review examines the specific effects of exercise training in relation to body composition and physical function demonstrated by changes in cardiovascular fitness, and muscle strength when obese adults undergo energy restriction.
Electronic databases were searched for randomised controlled trials comparing energy restriction plus exercise training to energy restriction alone. Studies published to May 2013 were included if they used multi-component methods for analysing body composition and assessed measures of fitness in obese adults.
Fourteen RCTs met the inclusion criteria. Heterogeneity of study characteristics prevented meta-analysis. Energy restriction plus exercise training was more effective than energy restriction alone for improving cardiovascular fitness, muscle strength, and increasing fat mass loss and preserving lean body mass, depending on the type of exercise training.
Adding exercise training to energy restriction for obese middle-aged and older individuals results in favourable changes to fitness and body composition. Whilst weight loss should be encouraged for obese individuals, exercise training should be included in lifestyle interventions as it offers additional benefits.
Journal Article
The effect of prednisolone ingestion and acute exercise on lipocalin-2 and its variants in young men: a pilot randomised crossover study
2025
Lipocalin-2 (LCN2) has three main variants; polyaminated (hLCN2) and non-polyaminated (C87A and R81E). The polyaminated form is proposed to positively influence energy control, whereas the non-polyaminated forms negatively impact energy control in mice. Glucocorticoids negatively affect glucose regulation and exercise has a positive effect. We hypothesise that glucocorticoids will suppress, while exercise will increase hLCN2, and decrease C87A and R81E, which will be associated with improved insulin sensitivity. In a randomised crossover design, nine young healthy men (aged 27.8 ± 4.9 years; BMI 24.4 ± 2.4 kg/m
2
) completed 30 min of high-intensity aerobic exercise (90–95% heart rate reserve) after glucocorticoid or placebo ingestion. Blood was collected and analyzed for LCN2 and its variants levels at baseline, immediately, 60 min and 180 min post-exercise. Insulin sensitivity was assessed using hyperinsulinemic-euglycemic clamp. A main effect, increase in LCN2 was detected for prednisolone ingestion (overall treatment effect
p
= 0.001), but not LCN2 variants (all
p
> 0.05). Main effects for time were observed for exercise for LCN2 and all variants (overall time effect all
p
< 0.02). Regardless of treatment, LCN2, C87A, R81E, and hLCN2 increased immediately after exercise compared with baseline (all
p
< 0.04). C87A, but not LCN2 or its other variants, remained elevated at 180 min post-ex (
p
= 0.007). LCN2, but not its variants, was elevated in response to prednisolone ingestion. LCN2 and its variants are transiently increased by acute exercise, but this increase was not related to insulin sensitivity. The clinical implication of elevated LCN2 and its variants post-exercise on satiety and energy regulation, as well as the mechanisms involved warrant further investigation.
Clinical trial registration
:
www.anzctr.org.au
, ACTRN12615000755538.
Journal Article
The effect of exercise-intensity on skeletal muscle stress kinase and insulin protein signaling
by
Shaw, Christopher S.
,
Trewin, Adam
,
Stepto, Nigel K.
in
Activation
,
Adaptation
,
Adaptation, Physiological
2017
Stress and mitogen activated protein kinase (SAPK) signaling play an important role in glucose homeostasis and the physiological adaptation to exercise. However, the effects of acute high-intensity interval exercise (HIIE) and sprint interval exercise (SIE) on activation of these signaling pathways are unclear.
Eight young and recreationally active adults performed a single cycling session of HIIE (5 x 4 minutes at 75% Wmax), SIE (4 x 30 second Wingate sprints), and continuous moderate-intensity exercise work-matched to HIIE (CMIE; 30 minutes at 50% of Wmax), separated by a minimum of 1 week. Skeletal muscle SAPK and insulin protein signaling were measured immediately, and 3 hours after exercise.
SIE elicited greater skeletal muscle NF-κB p65 phosphorylation immediately after exercise (SIE: ~40%; HIIE: ~4%; CMIE; ~13%; p < 0.05) compared to HIIE and CMIE. AS160Ser588 phosphorylation decreased immediately after HIIE (~-27%; p < 0.05), and decreased to the greatest extent immediately after SIE (~-60%; p < 0.05). Skeletal muscle JNK (~42%; p < 0.05) and p38 MAPK (~171%; p < 0.05) phosphorylation increased, and skeletal muscle AktSer473 phosphorylation (~-32%; p < 0.05) decreased, to a similar extent immediately after all exercise protocols. AS160Ser588 phosphorylation was similar to baseline three hours after SIE (~-12%; p > 0.05), remained lower 3 hours after HIIE (~-34%; p < 0.05), and decreased 3 hours after CMIE (~-33%; p < 0.05).
Despite consisting of less total work than CMIE and HIIE, SIE proved to be an effective stimulus for the activation of stress protein kinase signaling pathways linked to exercise-mediated adaptation of skeletal muscle. Furthermore, post-exercise AS160Ser588 phosphorylation decreased in an exercise-intensity and post-exercise time-course dependent manner.
Journal Article
Exercise intensity matters: A review on evaluating the effects of aerobic exercise intensity on muscle‐derived neuroprotective myokines
2025
Exercise as a medical intervention is effective to help prevent and manage many chronic and complex diseases, including dementia. There is evidence to suggest that regular aerobic exercise protects against age‐related brain atrophy and reduces the risk of cognitive decline. The mechanisms by which exercise infers a neuroprotective effect remain to be established but may be related to a maintenance of brain volume and neuronal survival, improved cerebrovascular density and function, and/or increased synaptic plasticity. In addition, there is growing evidence to suggest the beneficial effects of exercise on brain health and cognitive function are, at least in part, mediated by factors released by skeletal muscle during contraction. The fact that the brain responds to exercise suggests that muscle‐derived peripheral factors, or “myokines,” may play a key role in muscle–brain crosstalk and exercise neuroprotection. However, the most effective “dose” of aerobic exercise to promote beneficial changes in these myokine pathways is currently unknown. Specifically, most of the evidence to date is from studies that have used moderate‐intensity exercise, and research investigating the merit of high‐intensity exercise is scarce. Considering the well‐established role of high‐intensity interval training in protecting against numerous medical conditions, more research is needed to identify the most effective “dose” of exercise to improve the beneficial effects of these myokines. Highlights Neuroprotection through exercise: Regular aerobic exercise mitigates age‐related brain atrophy and cognitive decline via multiple mechanisms, including brain volume maintenance, improved cerebrovascular function, and synaptic plasticity. Myokines as mediators: Muscle‐derived factors (myokines) play a crucial role in muscle–brain crosstalk, significantly contributing to the neuroprotective effects of exercise. Intensity matters: The review underscores the necessity to define and study exercise intensity, revealing high‐intensity exercise may be as effective, if not more, in promoting neuroprotective myokine levels compared to moderate‐intensity exercise. Future research directions: This review emphasizes the need for well‐controlled studies to explore the optimal exercise dose for enhancing myokine pathways and their implications for neurodegenerative disease prevention.
Journal Article
Exercise & Sports Science Australia (ESSA) position statement on exercise and chronic kidney disease
2013
Chronic kidney disease (CKD) is prevalent, affecting 13% of adult Australians and poses increased risk for cardiovascular morbidity and mortality. This position article provides evidence-based guidelines on the role of exercise training for CKD patients and provides recommendations for prescribing and delivering exercise training.
Position stand.
Synthesis of published work within the field of exercise training and chronic kidney disease.
Exercise training likely to provide benefits to CKD patients, including improvements in cardio-respiratory fitness, quality of life, sympatho-adrenal activity, muscle strength and increased energy intake and possible reduction in inflammatory biomarkers. Existing studies generally report small sample sizes, brief training periods and relatively high attrition rates. Exercise training appears to be safe for CKD patients with no deaths directly related to exercise training in over 30,000 patient-hours, although strict medical exclusion criteria in previous studies resulted in 25% of patients being excluded potentially impacting the generalisability of the findings.
Aerobic exercise at an intensity of >60% of maximum capacity is recommended to improve cardio-respiratory fitness. Few data are available on resistance training and it is unclear whether this form of training retards catabolic/inflammatory processes typical of CKD. However, it should be considered important due to its proven beneficial effects on bone density and muscle mass. Due to the high prevalence and incidence of co-morbidities in CKD patients, exercise training programs should be prescribed and delivered by individuals with appropriate qualifications and experience to recognise and accommodate co-morbidities and associated complications.
Journal Article
Undercarboxylated osteocalcin is associated with vascular function in female older adults but does not influence vascular function in male rabbit carotid artery ex vivo
2020
There are conflicting reports on the association of undercarboxylated osteocalcin (ucOC) in cardiovascular disease development, including endothelial function and hypertension. We tested whether ucOC is related to blood pressure and endothelial function in older adults, and if ucOC directly affects endothelial-mediated vasodilation in the carotid artery of rabbits.
In older adults, ucOC, blood pressure, pulse wave velocity (PWV) and brachial artery flow-mediated dilation (BAFMD) were measured (n = 38, 26 post-menopausal women and 12 men, mean age 73 ± 0.96). The vasoactivity of the carotid artery was assessed in male New Zealand White rabbits following a four-week normal or atherogenic diet using perfusion myography. An ucOC dose response curve (0.3-45 ng/ml) was generated following incubation of the arteries for 2-hours in either normal or high glucose conditions.
ucOC levels were higher in normotensive older adults compared to those with stage 2 hypertension (p < 0.05), particularly in women (p < 0.01). In all participants, higher ucOC was associated with lower PWV (p < 0.05), but not BAFMD (p > 0.05). In rabbits, ucOC at any dose did not alter vasoactivity of the carotid artery, either following a normal or an atherogenic diet (p > 0.05).
Increased ucOC is associated with lower blood pressure and increased arterial stiffness, particularly in post-menopausal women. However, ucOC administration has no direct short-term effect on endothelial function in rabbit arteries. Future studies should explore whether treatment with ucOC, in vivo, has direct or indirect effects on blood vessel function.
Journal Article
Psychological Responses to Acute Aerobic, Resistance, or Combined Exercise in Healthy and Overweight Individuals: A Systematic Review
by
Itamar Levinger
,
Samantha Cassar
,
Thomas J Elkington
in
Aerobics
,
Authorship
,
Body mass index
2017
INTRODUCTION: Psychological distress and depression are risk factors for cardiovascular disease (CVD). As such, a reduction in psychological distress and increase in positive well-being may be important to reduce the risk for future development of CVD. Exercise training may be a good strategy to prevent and assist in the management of psychological disorders. The psychological effects of the initial exercise sessions may be important to increase exercise adherence. The aims of this systematic review were (a) to examine whether acute aerobic, resistance, or a combination of the 2 exercises improves psychological well-being and reduces psychological distress in individuals with healthy weight and those who are overweight/obese but free from psychological disorders, and (b) if so, to examine which form of exercise might yield superior results. METHODS: The online database PubMed was searched for articles using the PICO (patient, intervention, comparison, and outcome) framework for finding scientific journals based on key terms. RESULTS: Forty-two exercise studies met the inclusion criteria. A total of 2187 participants were included (age: 18-64 years, body mass index [BMI]: 21-39 kg/m2). Only 6 studies included participants with a BMI in the overweight/obese classification. Thirty-seven studies included aerobic exercise, 2 included resistance exercise, 1 used a combination of aerobic and resistance, and 2 compared the effects of acute aerobic exercise versus the effects of acute resistance exercise. The main findings of the review were that acute aerobic exercise improves positive well-being and have the potential to reduce psychological distress and could help reduce the risks of future CVD. However, due to the limited number of studies, it is still unclear which form of exercise yields superior psychological benefits. CONCLUSIONS: Obese, overweight, and healthy weight individuals can exhibit psychological benefits from exercise in a single acute exercise session, and these positive benefits of exercise should be used by health professionals as a tool to increase long-term participation in exercise in these populations.
Journal Article
Prevalence of diagnosable depression in patients awaiting orthopaedic specialist consultation: a cross-sectional analysis
2023
Background
Musculoskeletal conditions, including osteoarthritis (OA), are a leading cause of disability and chronic pain, and are associated with high rates of comorbid depression. However, signs of depression are often masked by pain. The aim of this study was to determine the prevalence and severity of depression and pain in individuals awaiting specialist orthopaedic consultation. A secondary objective was to determine the relationship between pain and depression, irrespective of demographic factors and clinical diagnosis.
Methods
Cross-sectional analysis of individuals awaiting orthopaedic consultation at a public hospital in Melbourne, Australia. Relevant data were extracted from medical records and questionnaires. Descriptive statistics were used to summarise participant characteristics. The patient health questionnaire (PHQ-9) was used to assess depression and a numerical rating scale (NRS) was used to assess pain severity. Multiple linear regression analyses were used to establish the relationship between pain and depression.
Results
Nine hundred and eighty-six adults (mean ± standard deviation, age = 54.1 ± 15.7 years, 53.2% women) participated in the study. OA was present in 56% of the population and 34% of the entire population had moderate depression or greater, 19% of which met the criteria for major depressive disorder. Moderate-to-severe pain was present in 79% of individuals with OA and 55% of individuals with other musculoskeletal complaints. Pain was significantly associated with depression scores (β = 0.84, adjusted R
2
= 0.13, P < 0.001), and this relationship remained significant after accounting for gender, age, education and employment status, OA status, number of joints affected and waiting time (β = 0.91, adjusted R
2
= 0.19, P < 0.001).
Conclusions
Depression affects one-third of individuals on an orthopaedic waitlist. A strong link between pain and depression in patients awaiting specialist orthopaedic consultation exists, indicating a need for an integrated approach in addressing pain management and depression to manage this complex and comorbid presentation.
Journal Article