Mathieu Maltais

Synergic effect of phytoestrogens and exercise training on cardiovascular risk profile in exercise-responder postmenopausal women: a pilot study.

Objective: We showed that isoflavones and exercise improve total and abdominal fat mass (FM) to a greater extent than does exercise alone in postmenopausal women, but not other cardiovascular disease (CVD) risk factors. Fat-free mass (FFM) showed a wide variability of responses, with 60% of women having increased FFM and 40% having decreased FFM. We thus wondered if women who had decreased FFM could be considered as nonresponders (NRs) to exercise and if this masked a potential synergistic effect of phytoestrogens (PHY) and exercise. The aim of this study was to verify if PHYs enhance the response obtained after aerobic and resistance exercises in CVD risk profile in exercise responders. Methods: Among 21 women who participated in a 6-month exercise program and received PHY or placebo (PLA), 14 were exercise responders (PHY, n = 8; PLA, n = 6) whereas 7 were NRs. Body weight, waist circumference, FM, and FFM were assessed (dual-energy x-ray absorptiometry). Plasma glucose, insulin, sex hormone-binding globulin, and testosterone levels were obtained after a 12-hour overnight fast. Total energy intake was measured with a 3-day dietary record. All measurements were performed before and after the intervention. Results: After exercise training, the PHY and PLA groups, but not the NR group, had increased FFM (0.01 < P < 0.03). On the other hand, body weight, FM, and systolic and diastolic blood pressure (0.01 < P < 0.05) decreased in the PHY group only. Furthermore, plasma insulin level (P = 0.04) and homeostasis model assessment significantly decreased (P = 0.03) while plasma sex hormone-binding globulin increased (P = 0.04) after training in the PHY group, whereas energy intake remained unchanged in both groups (0.10 < P < 0.59) after the intervention. Conclusion: PHYs combined with exercise compared with exercise alone seem to improve body composition and CVD risk profile in exercise-responder women.

The Effect of Resistance Training and Different Sources of Postexercise Protein Supplementation on Muscle Mass and Physical Capacity in Sarcopenic Elderly Men.

Abstract Maltais, ML, Ladouceur, JP, and Dionne, IJ. The effect of resistance training and different sources of postexercise protein supplementation on muscle mass and physical capacity in sarcopenic elderly men. J Strength Cond Res 30(6): 1680–1687, 2016—The loss of muscle mass (sarcopenia) with aging is related to a progressive loss of muscle strength and physical capacity. Resistance exercise and milk-based protein supplementation have been demonstrated as significant countermeasures for sarcopenia and the loss of muscle strength. However, using high doses of proteins can act as a meal replacement in the elderly. Therefore, we sought to determine whether a standard supplementation (12 g per serving) of protein and resistance training could be an efficient strategy to promote muscle strength and physical capacity in sarcopenic men. Twenty-six participants were randomized in 3 groups in a double-blind control study. All the groups performed exercise and consumed a protein-rich supplement 12 g of protein, 7 g of essential amino acids from milk (n = 8), soy (n = 8), or rice milk (nonprotein control, n = 10). Body composition was measured using dual-energy x-ray absorptiometry. Strength was measured by 1 repetition maximum with different exercises. Different physical capacity measurements were assessed (timed up and go test, chair stand, and walking speed). The results indicated a significant increase in fat-free mass in all groups and changes in muscle strength, with no differences between groups. This study indicates that resistance training is an effective way to increase muscle mass and strength, regardless of protein supplementation. Higher doses of protein-rich foods may have to be recommended to promote muscle mass gains when executing resistance exercise in elderly sarcopenic individuals.

Effect of Resistance Training and Various Sources of Protein Supplementation on Body Fat Mass and Metabolic Profile in Sarcopenic Overweight Older Adult Men: A Pilot Study.

The decrease in resting energy expenditure (REE) and fat oxidation with aging is associated with an increase in fat mass (FM), and both could be prevented by exercise such as resistance training. Dairy consumption has also been shown to promote FM loss in different subpopulations and to be positively associated with fat oxidation. Therefore, we sought to determine whether resistance exercise combined with dairy supplementation could have an additive impact on FM and energy metabolism, especially in individuals with a deficit in muscle mass. Twenty-six older overweight sarcopenic men (65 ± 5 years old) were recruited for the study. They participated in 4 months of resistance exercise and were randomized into three groups for postexercise shakes (control, dairy, and nondairy isocaloric and isoprotein supplement with 375 ml and ~280 calories per shake). Body composition was measured by dual X-ray absorptiometry and REE by indirect calorimetry. Fasting glucose, insulin, leptin, inflammatory profile, and blood lipid profile were also measured. Significant decreases were observed with FM only in the dairy supplement group; no changes were observed for any other variables. To conclude, FM may decrease without changes in metabolic parameters during resistance training and dairy supplementation with no caloric restriction without having any impact on metabolic properties. More studies are warranted to explain this significant decrease in FM.The decrease in resting energy expenditure (REE) and fat oxidation with aging is associated with an increase in fat mass (FM), and both could be prevented by exercise such as resistance training. Dairy consumption has also been shown to promote FM loss in different subpopulations and to be positively associated with fat oxidation. Therefore, we sought to determine whether resistance exercise combined with dairy supplementation could have an additive impact on FM and energy metabolism, especially in individuals with a deficit in muscle mass. Twenty-six older overweight sarcopenic men (65 ± 5 years old) were recruited for the study. They participated in 4 months of resistance exercise and were randomized into three groups for postexercise shakes (control, dairy, and nondairy isocaloric and isoprotein supplement with 375 ml and ~280 calories per shake). Body composition was measured by dual X-ray absorptiometry and REE by indirect calorimetry. Fasting glucose, insulin, leptin, inflammatory profile, and blood lipid profile were also measured. Significant decreases were observed with FM only in the dairy supplement group; no changes were observed for any other variables. To conclude, FM may decrease without changes in metabolic parameters during resistance training and dairy supplementation with no caloric restriction without having any impact on metabolic properties. More studies are warranted to explain this significant decrease in FM.

Is Fat Mass Cross-Sectionally Associated with Cortical Aβ Load in the Human Brain?

ObjectivesThe objective of this study was to examine the relationship of fat mass (FM) with brain amyloid (Aβ) load in older adults.MethodsData from the Multidomain Alzheimer’s Preventive Trial (MAPT) for Positron emission tomography and dual-energy X-ray absorptiometry (DXA) were used. Linear regressions controlling for appendicular muscle, age, education, clinical dementia rating scale and Apolipoprotein-E were performed to explore the relationships between FM, trunk FM and Aβ-load.ResultsThirty-nine participants (75.7 ± 4.2 years old) with an average BMI of 27.5 ± 4.0 kg/m2 were analyzed in this study. There were significant and positive associations of both total and trunk FM with Aβ load [0.01 (0.002-0.02) and 0.02 (0.001-0.04), respectively]; however, when adding ApoE-ε4 as a confounder, associations were no longer significant.ConclusionsThis study has found associations between FM as measured by DXA and cerebral Aβ load, suggesting that excessive FM might be involved in AD pathology.

A short-term intervention combining aerobic exercise with medium-chain triglyceride (MCT) is more ketogenic than either MCT or aerobic exercise alone: A comparison of normoglycemic and pre-diabetic older women.

The objectives of this study were to determine (i) whether a 5-day aerobic exercise (AE) program combined with a medium-chain triglyceride (MCT) supplement would increase the plasma ketone response in older women more than either intervention alone and (ii) whether ketonemia after these combined or separate treatments was alike in normoglycemic (NG) and prediabetic (PD) women. Older women (NG, n = 10; PD, n = 9) underwent a 4-h metabolic study after each of 4 different treatments: (i) no treatment (control), (ii) 5 days of MCT alone (30 g·day-1), (iii) 1 session of 30 min of AE alone, and (iv) 5 days of MCT and AE combined (MCT+AE). Blood was sampled every 30 min over 4 h for analysis. In NG, MCT+AE induced the highest area under the curve (AUC) for plasma ketones (835 ± 341 μmol·h·L-1); this value was 69% higher than that observed with MCT alone (P < 0.05). AUCs were not different between MCT alone and MCT+AE in PD, but both treatments induced a significantly higher AUC than the control or AE alone (P < 0.05). Although there was a trend towards a higher ketone AUC in NG versus PD with AE alone (P = 0.091), there was no significant difference between the ketone AUCs in PD and NG. In conclusion, MCT+AE was more ketogenic in older women than MCT or AE alone. MCT+AE had a synergistic effect on ketonemia in NG but not in PD. Whether improving insulin sensitivity with a longer term AE intervention can improve the ketogenic effect of MCT in PD and thereby increase brain ketone uptake in older people merits further investigation.

Six-month observational follow-up on activities of daily living in people with dementia living in nursing homes after a 6-month group based on either exercise or social activities

BackgroundStudies have demonstrated changes in activities of daily living after an exercise intervention in people with dementia (PWD) living in nursing homes (NH). However, some discrepancies are shown during follow-up.AimsOur objective was to measure activities of daily living (ADL) performance during a 6-month observational follow-up after a 6-month exercise or social activity intervention in PWD living in NH.MethodsAfter cluster randomisation, 91 PWD living in NH performed a 6-month structured exercise intervention (n = 44) or a social activity intervention (n = 47). After the intervention, 85 PWD were assessed for post-intervention follow-up. Instrumental and basic activities of daily living (IADL, ADL) were measured at 6-month observational follow-up after the intervention using the Alzheimer’s Disease Cooperative Study Activities of Daily Living Inventory for Severe Alzheimer’s Disease (ADCS-ADL-sev) scale (scores ranging from 0 to 51, higher is better).ResultsCompared to participants in the social activity, those who participated to the exercise intervention had a significant decrease of their ADCS-ADL-sev score (between-group adjusted mean difference: 4.6 points, p = 0.001) with IADL having the most decrease (2.8 points, p = 0.004).DiscussionUnexpectedly, exercisers declined sharply in the performance of ADLs and IADLs, whereas participants in the social intervention group maintained their levels. The potential mechanisms to explain these findings remain still to be elucidated.