Jacinda Meiklejohn

The Study of Mental and Resistance Training (SMART) study—resistance training and/or cognitive training in mild cognitive impairment: a randomized, double-blind, double-sham controlled trial.

BACKGROUND Mild cognitive impairment (MCI) increases dementia risk with no pharmacologic treatment available. METHODS The Study of Mental and Resistance Training was a randomized, double-blind, double-sham controlled trial of adults with MCI. Participants were randomized to 2 supervised interventions: active or sham physical training (high intensity progressive resistance training vs seated calisthenics) plus active or sham cognitive training (computerized, multidomain cognitive training vs watching videos/quizzes), 2-3 days/week for 6 months with 18-month follow-up. Primary outcomes were global cognitive function (Alzheimers Disease Assessment Scale-cognitive subscale; ADAS-Cog) and functional independence (Bayer Activities of Daily Living). Secondary outcomes included executive function, memory, and speed/attention tests, and cognitive domain scores. RESULTS One hundred adults with MCI [70.1 (6.7) years; 68% women] were enrolled and analyzed. Resistance training significantly improved the primary outcome ADAS-Cog; [relative effect size (95% confidence interval) -0.33 (-0.73, 0.06); P < .05] at 6 months and executive function (Wechsler Adult Intelligence Scale Matrices; P = .016) across 18 months. Normal ADAS-Cog scores occurred in 48% (24/49) after resistance training vs 27% (14/51) without resistance training [P < .03; odds ratio (95% confidence interval) 3.50 (1.18, 10.48)]. Cognitive training only attenuated decline in Memory Domain at 6 months (P < .02). Resistance training 18-month benefit was 74% higher (P = .02) for Executive Domain compared with combined training [z-score change = 0.42 (0.22, 0.63) resistance training vs 0.11 (-0.60, 0.28) combined] and 48% higher (P < .04) for Global Domain [z-score change = .0.45 (0.29, 0.61) resistance training vs 0.23 (0.10, 0.36) combined]. CONCLUSIONS Resistance training significantly improved global cognitive function, with maintenance of executive and global benefits over 18 months.

Changes in insulin resistance and HbA1c are related to exercise-mediated changes in body composition in older adults with type 2 diabetes: interim outcomes from the GREAT2DO trial.

OBJECTIVE To investigate changes in body composition after 12 months of high-intensity progressive resistance training (PRT) in relation to changes in insulin resistance (IR) or glucose homeostasis in older adults with type 2 diabetes. RESEARCH DESIGN AND METHODS One-hundred three participants were randomized to receive either PRT or sham exercise 3 days per week for 12 months. Homeostasis model assessment 2 of insulin resistance (HOMA2-IR) and glycosylated hemoglobin (HbA1c) were used as indices of IR and glucose homeostasis. Skeletal muscle mass (SkMM) and total fat mass were assessed using bioelectrical impedance. Visceral adipose tissue, mid-thigh cross-sectional area, and mid-thigh muscle attenuation were quantified using computed tomography. RESULTS Within the PRT group, changes in HOMA2-IR were associated with changes in SkMM (r = −0.38; P = 0.04) and fat mass (r = 0.42; P = 0.02). Changes in visceral adipose tissue tended to be related to changes in HOMA2-IR (r = 0.35; P = 0.07). Changes in HbA1c were related to changes in mid-thigh muscle attenuation (r = 0.52; P = 0.001). None of these relationships were present in the sham group (P > 0.05). Using ANCOVA models, participants in the PRT group who had increased SkMM had decreased HOMA2-IR (P = 0.05) and HbA1c (P = 0.09) compared with those in the PRT group who lost SkMM. Increases in SkMM in the PRT group decreased HOMA2-IR (P = 0.07) and HbA1c (P < 0.05) compared with those who had increased SkMM in the sham group. CONCLUSIONS Improvements in metabolic health in older adults with type 2 diabetes were mediated through improvements in body composition only if they were achieved through high-intensity PRT.

Mediation of Cognitive Function Improvements by Strength Gains After Resistance Training in Older Adults with Mild Cognitive Impairment: Outcomes of the Study of Mental and Resistance Training

To determine whether improvements in aerobic capacity (VO2peak) and strength after progressive resistance training (PRT) mediate improvements in cognitive function.

Midlife managerial experience is linked to late life hippocampal morphology and function

An active cognitive lifestyle has been suggested to have a protective role in the long-term maintenance of cognition. Amongst healthy older adults, more managerial or supervisory experiences in midlife are linked to a slower hippocampal atrophy rate in late life. Yet whether similar links exist in individuals with Mild Cognitive Impairment (MCI) is not known, nor whether these differences have any functional implications. 68 volunteers from the Sydney SMART Trial, diagnosed with non-amnestic MCI, were divided into high and low managerial experience (HME/LME) during their working life. All participants underwent neuropsychological testing, structural and resting-state functional MRI. Group comparisons were performed on hippocampal volume, morphology, hippocampal seed-based functional connectivity, memory and executive function and self-ratings of memory proficiency. HME was linked to better memory function (p = 0.024), mediated by larger hippocampal volume (p = 0.025). More specifically, deformation analysis found HME had relatively more volume in the CA1 sub-region of the hippocampus (p < 0.05). Paradoxically, this group rated their memory proficiency worse (p = 0.004), a result correlated with diminished functional connectivity between the right hippocampus and right prefrontal cortex (p < 0.001). Finally, hierarchical regression modelling substantiated this double dissociation.

Train High Eat Low for Osteoarthritis study (THE LO study): protocol for a randomized controlled trial.

INTRODUCTION Osteoarthritis (OA) is one of the most prevalent chronic conditions among older adults, with the medial tibio-femoral joint being most frequently affected. The knee adduction moment is recognized as a surrogate measure of the medial tibio-femoral compartment joint load and therefore represents a valid intervention target. This article provides the rationale and methodology for THE LO study (Train High, Eat Low for Osteoarthritis), which is a randomized controlled trial that is investigating the effects of a unique, targeted lifestyle intervention in overweight/obese adults with symptomatic medial knee OA. RESEARCH QUESTION Compared to a control group given only lifestyle advice, do the effects of the following interventions result in significant reductions in the knee adduction moment: (1) gait retraining; and (2) combined intervention (which involves a combination of three interventions: (a) gait retraining, (b) high-intensity progressive resistance training, and (c) high-protein/low-glycaemic-index energy-restricted diet)? It is hypothesized that the combined intervention group will be superior to the isolated interventions of the high-protein/low-glycaemic-index diet group and the progressive resistance training group. Finally, it is hypothesized that the combined intervention will result in a greater range of improvements in secondary outcomes, including: muscle strength, functional status, body composition, metabolic profile, and psychological wellbeing, compared to any of the isolated interventions or control group. DESIGN Single-blinded, randomized controlled trial adhering to the CONSORT guidelines on conduct and reporting of non-pharmacological clinical trials. PARTICIPANTS One hundred and twenty-five community-dwelling people are being recruited. Inclusion criteria include: medial knee OA, low physical activity levels, no current resistance training, body mass index ≥ 25kg/m(2) and age ≥ 40 years. INTERVENTION AND CONTROL The participants are stratified by sex and body mass index, and randomized into one of five groups: (1) gait retraining; (2) progressive resistance training; (3) high-protein/low-glycaemic-index energy-restricted diet (25 to 30% of energy from protein, 45% of energy from carbohydrates, < 30% of energy from fat, and glycaemic index diet value < 50); (4) a combination of these three active interventions; or (5) a lifestyle-advice control group. All participants receive weekly telephone checks for health status, adverse events and optimisation of compliance. MEASUREMENTS Outcomes are measured at baseline, 6 and 12 months. The primary outcome is the peak knee adduction moment during the early stance phase of gait. The secondary outcome measures are both structural (radiological), with longitudinal reduction in medial minimal joint space width at 12 months, and clinical, including: change in body mass index; joint pain, stiffness and function; body composition; muscle strength; physical performance/mobility; nutritional intake; habitual physical activity and sedentary behaviour; sleep quality; psychological wellbeing and quality of life. DISCUSSION THE LO study will provide the first direct comparison of the long-term benefits of gait retraining, progressive resistance training and a high-protein/low-glycaemic-index energy-restricted diet, separately and in combination, on joint load, radiographic progression, symptoms, and associated co-morbidities in overweight/obese adults with OA of the knee.