Can Undergraduate Students Help Change Older Adults' Confidence for Making Nutrition-Related Decisions in a 45-Minute Nutrition Workshop?

Purpose: The Social Cognitive Theory (SCT) suggests health behaviour can be modified by enhancing knowledge of health benefits and outcome expectations of changing behaviour, improving self-efficacy (confidence), and developing goals to overcome barriers to behaviour change. This study aimed to determine the impact of student-led nutrition workshops on participants' confidence related to SCT constructs for making dietary choices that align with evidence-based nutrition recommendations.Methods: Level-4 Science students developed and delivered 9 workshops on nutrition recommendations for the prevention and management of age-related diseases. Participants attending the workshops completed pre- and post-surveys to assess SCT constructs. For each SCT construct, participants rated their confidence on a 10-point Likert scale. The number (%) of participants who rated their confidence as ≥8/10 on the pre- and post-surveys were compared using the χ2 test.Results: Sixty-three community members (60% female, mean ± SD age 71 ± 7 years) attended the workshops. The number of participants rating confidence as ≥8/10 for each SCT construct increased after the workshops (P < 0.05).Conclusion: Undergraduate students can positively influence community members' confidence for making nutrition-related decisions. Involving students in interventions where SCT-structured workshops are used may help conserve health care resources and reach older adults who may not have access to dietitian services.

The reliability of a segmentation methodology for assessing intramuscular adipose tissue and other soft-tissue compartments of lower leg MRI images.

OBJECTIVE: Determine the reliability of a magnetic resonance (MR) image segmentation protocol for quantifying intramuscular adipose tissue (IntraMAT), subcutaneous adipose tissue, total muscle and intermuscular adipose tissue (InterMAT) of the lower leg. MATERIALS AND METHODS: Ten axial lower leg MRI slices were obtained from 21 postmenopausal women using a 1 Tesla peripheral MRI system. Images were analyzed using sliceOmatic™ software. The average cross-sectional areas of the tissues were computed for the ten slices. Intra-rater and inter-rater reliability were determined and expressed as the standard error of measurement (SEM) (absolute reliability) and intraclass coefficient (ICC) (relative reliability). RESULTS: Intra-rater and inter-rater reliability for IntraMAT were 0.991 (95% confidence interval [CI] 0.978-0.996, p < 0.05) and 0.983 (95% CI 0.958-9.993, p < 0.05), respectively. For the other soft tissue compartments, the ICCs were all >0.90 (p < 0.05). The absolute intra-rater and inter-rater reliability (expressed as SEM) for segmenting IntraMAT were 22.19 mm(2) (95% CI 16.97-32.04) and 78.89 mm(2) (95% CI 60.36-113.92), respectively. CONCLUSION: This is a reliable segmentation protocol for quantifying IntraMAT and other soft-tissue compartments of the lower leg. A standard operating procedure manual is provided to assist users, and SEM values can be used to estimate sample size and determine confidence in repeated measurements in future research.

Changes in trabecular bone microarchitecture in postmenopausal women with and without type 2 diabetes: a two year longitudinal study.

BACKGROUND: The risk of experiencing an osteoporotic fracture is greater for adults with type 2 diabetes despite higher than normal bone mineral density (BMD). In addition to BMD, trabecular bone microarchitecture contributes to bone strength, but is not assessed using conventional BMD measurement by dual x-ray absorptiometry (DXA). The aim of this study was to compare two year changes in trabecular bone microarchitecture in women with and without type 2 diabetes. METHODS: We used a 1 Tesla magnetic resonance imaging (MRI) scanner to acquire axial images (resolution 195 µm × 195 µm × 1000 µm) of the distal radius. We report the change in the number and size of trabecular bone holes, bone volume fraction (BVTV), trabecular thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp), endosteal area, nodal and branch density for each group. Lumbar spine and proximal femur BMD were measured with DXA (Hologic, Discovery QDR4500A) at baseline and follow-up. Using a multivariable linear regression model, we evaluated whether the percent change in the trabecular bone microarchitecture variables differed between women with and without type 2 diabetes. RESULTS: Of the 54 participants at baseline with valid MRI image sets, 37 participants (baseline mean [SD] age, 70.8 [4.4] years) returned for follow-up assessment after 25.4 [1.9] months. Lumbar spine BMD was greater for women with diabetes compared to without diabetes at both baseline and follow-up. After adjustment for ethnicity, women with diabetes had a higher percent increase in number of trabecular bone holes compared to controls (10[1] % versus -7 [2]%, p=0.010), however results were no longer significant after adjustment for multiple comparisons (p=0.090). There were no differences in the change in other trabecular bone microarchitecture variables between groups. CONCLUSION: There were no differences in percent change in trabecular bone microarchitecture variables over two years in women with type 2 diabetes compared to women without diabetes. This study provides feasibility data, which will inform future trials assessing change in trabecular bone microarchitecture in women with type 2 diabetes. Larger studies using higher resolution imaging modalities that can assess change in trabecular and cortical bone compartments in women with type 2 diabetes are needed.

Prevalence of sarcopenia indicators and sub-optimal protein intake among elective total joint replacement patients.

Sarcopenia is associated with falls, and can complicate recovery following total joint replacement (TJR) surgery. We examined (1) the prevalence of sarcopenia indicators and lower-than-recommended protein intake among TJR patients and non-TJR community participants and (2) the relationships between dietary protein intake and sarcopenia indicators. We recruited adults ≥65 years of age who were undergoing TJR, and adults from the community not undergoing TJR (controls). We assessed grip strength and appendicular lean soft-tissue mass (ALSTMBMI) using DXA, and applied the original Foundation for the National Institutes of Health Sarcopenia Project cut-points for sarcopenia indicators (grip strength <26 kg for men and <16 kg for women; ALSTM <0.789 m2 for men and <0.512 m2 for women) and less conservative cut-points (grip strength <31.83 kg for men and <19.99 kg for women; ALSTM <0.725 m2 for men and <0.591 m2 for women). Total daily and per meal protein intakes were derived from 5-day diet records. Sixty-seven participants (30 TJR, 37 controls) were enrolled. Using less conservative cut-points for sarcopenia, more control participants were weak compared with TJR participants (46% versus 23%, p = 0.055), and more TJR participants had low ALSTMBMI (40% versus 13%, p = 0.013). Approximately 70% of controls and 76% of TJR participants consumed <1.2 g protein/kg/day (p = 0.559). Total daily dietary protein intake was positively associated with grip strength (r = 0.44, p = 0.001) and ALSTMBMI (r = 0.29, p = 0.03). Using less conservative cut-points, low ALSTMBMI, but not weakness, was more common in TJR patients. Both groups may benefit from a dietary intervention to increase protein intake, which may improve surgical outcomes in TJR patients.

Muscle Architecture and Subcutaneous Fat Measurements of Rectus Femoris and Vastus Lateralis at Optimal Length Aided by a Novel Ultrasound Transducer Attachment.

Purpose: This cross-sectional study determines the sensitivity of muscle architecture and fat measurements of the rectus femoris (RF) and vastus lateralis (VL) muscles from ultrasound images acquired with varying transducer tilt, using a novel transducer attachment, in healthy adults. Secondary objectives were to estimate intrarater and interrater reliability of image measurement and acquisition, respectively. Methods: Thirty healthy adults participated (15 women and 15 men; 25 [SD 2.5] y). Ultrasound image acquisition was conducted by two raters at different transducer tilts relative to the skin: estimated perpendicular, and five measured angles (80°, 85°, 90°, 95°, 100°) using the transducer attachment. Muscle thickness (MT), subcutaneous fat thickness (FT), pennation angle (PA), and fascicle length (FL) were measured. Sensitivity and reliability were assessed using intra-class correlation coefficients (ICCs) and standard error of measurements (SEMs). Results: MT and FT for RF and VL were not sensitive to transducer tilt. However, PA and FL were sensitive to transducer tilt. MT and FT for both muscles showed high ICCs and low SEMs for intrarater and interrater reliability. For PA of both muscles, standardizing transducer tilt improved interrater ICCs and lowered SEMs. Conclusion: MT and FT measurements of RF and VL acquired at 60° knee flexion are robust to varying transducer tilt angles. PA measurements benefit from standardizing transducer tilt.

Objectif : étude transversale pour déterminer la sensibilité de l'architecture musculaire et des mesures lipidiques du muscle droit antérieur de la cuisse (MDAC) et du muscle vaste externe (MVE) à partir des images échographiques acquises chez des adultes en santé par diverses inclinaisons du transducteur, au moyen d'un nouveau dispositif. Les objectifs secondaires consistaient à évaluer la fiabilité intraévaluateurs et interévaluateurs des mesures et de l'acquisition des images, respectivement. Méthodologie: au total, 30 adultes en santé ont participé (15 femmes et 15 hommes de 25 [ÉT 2,5 ans]). Deux évaluateurs ont acquis des images échographiques à des inclinaisons différentes du transducteur par rapport à la peau : mesure perpendiculaire estimative et mesure à cinq angles (80°, 85°, 90°, 95°, 100°) au moyen du dispositif du transducteur. Ils ont mesuré l'épaisseur des muscles (ÉM), l'épaisseur de la graisse sous-cutanée (ÉG), l'angle de pennation (AP) et la longueur des fascicules (LF). Ils ont aussi évalué la sensibilité et la fiabilité au moyen de coefficients de corrélation intraclasse (CCI) et de l'écart-type des mesures (ÉTM). Résultats: l'ÉM et l'ÉG du MDAC et du MVE n'étaient pas sensibles à l'inclinaison du transducteur, mais l'AP et la LF l'étaient. La fiabilité intraévaluateur et interévaluateur de l'ÉM et de l'ÉG des deux muscles présentait un CCI élevé et un ÉTM faible. Pour ce qui est de l'AP des deux muscles, la standardisation de l'inclinaison du transducteur améliorait la CCI et réduisait l'ÉTM interévaluateurs. Conclusion: les mesures de l'ÉM et de l'ÉG du MDAC et du MVE acquises à une flexion du genou de 60° sont probantes à des angles d'inclinaison variables du transducteur. Les mesures de l'AP tirent profit d'une inclinaison du transducteur standardisée.

Clinical risk factors for fracture in diabetes: a matched cohort analysis.

The objective was to determine which individuals with diabetes are at increased risk for fracture. It is unknown whether traditional clinical risk factors (CRFs) can be used in this population to identify individuals at higher risk of fracture. Using the Manitoba Bone Density Program database, we identified 3054 diabetic women and 9151 matched nondiabetic controls. The independent association of specific CRFs with incident osteoporotic fracture risk was assessed separately in those with diabetes and in controls, with subsequent examination of the interaction between diagnosed diabetes and each CRF. Prior major fractures were more prevalent in the diabetic group compared with the nondiabetic group (16.2% vs 14.3%, p<0.001). During mean 4 yr of observation, 259 (8.5%) of diabetic women and 559 (6.5%) of nondiabetic women experienced an incident major osteoporotic fracture (unadjusted hazard ratio [HR] for diabetes 1.49 [95% confidence interval (CI): 1.28-1.72], p<0.001; adjusted HR 1.14 [95% CI: 1.10-1.18], p<0.001). There were no significant differences between the 2 groups in the HRs for incident fracture associated with any of the CRFs studied (all p-for-interaction >0.1). Diabetes is a risk factor for major fracture. The ability of traditional CRFs to predict osteoporotic fractures is not influenced by the diagnosis of diabetes.

A randomized controlled trial of vitamin D dosing strategies after acute hip fracture: no advantage of loading doses over daily supplementation.

BACKGROUND: There remains uncertainty regarding the appropriate therapeutic management of hip fracture patients. The primary aim of our study was to examine whether large loading doses in addition to daily vitamin D offered any advantage over a simple daily low-dose vitamin D regimen for increasing vitamin D levels. METHODS: In this randomized controlled study, patients over age 50 with an acute fragility hip fracture were enrolled from two hospital sites in Ontario, Canada. Participants were randomized to one of three loading dose groups: placebo; 50,000 IU vitamin D2; or 100,000 IU D2. Following a placebo/loading dose, all patients received a daily tablet of 1,000 IU vitamin D3 for 90 days. Serum 25-hydroxy vitamin D (25-OHD) was measured at baseline, discharge from acute care (approximately 4-weeks), and 3-months. RESULTS: Sixty-five patients were enrolled in the study (44% male). An immediate rise in 25-OHD occurred in the 100,000 group, however there were no significant differences in 25-OHD between the placebo, 50,000 and 100,000 loading dose groups after 4-weeks (69.3, 84.5, 75.6 nmol/L, p = 0.15) and 3-months (86.7, 84.2, 73.3 nmol/L, p = 0.09), respectively. At the end of the study, approximately 75% of the placebo and 50,000 groups had reached the target therapeutic range (75 nmol/L), and 44% of the 100,000 group. CONCLUSIONS: In correcting vitamin D insufficiency/deficiency in elderly patients with hip fracture, our findings suggest that starting with a lower daily dose of Vitamin D3 achieved similar results as providing an additional large loading dose of Vitamin D2. At the end of the study, all three groups were equally effective in attaining improvement in 25-OHD levels. Given that a daily dose of 1,000 IU vitamin D3 (with or without a loading dose) resulted in at least 25% of patients having suboptimal vitamin D status, patients with acute hip fracture may benefit from a higher daily dose of vitamin D. TRIAL REGISTRATION: Clinical Trials # NCT00424619.

Promoting Osteoporosis Best Practices: A New Electronic Medical Record Tool.

Despite the high prevalence and devastating outcomes associated with osteoporotic fractures, they are not well investigated or treated. We developed an electronic Osteoporosis and Falls Assessment Form for integration within electronic medical records (EMR) with the aim to improve osteoporosis-related care in family practice. We examined usage and collected usability feedback from 37 physicians. A medical record review was used to assess tool usage over a 6-month period after which all participants completed a survey to assess their perceptions of the tool. The tool was used at least once by 22 (59%) physicians with 119 patients. Most users reported that it enhanced their practice (64%) and they intended to use it in the future (71%). Time constraints, complexity, and requirements to manually enter sections were identified as barriers to use. Lessons learned will inform improvements, which, given the perceived value of this tool, will likely improve uptake.

The Short Performance Physical Battery Is Associated with One-Year Emergency Department Visits and Hospitalization.

Les outils cliniques employés dans les établissements de soins peuvent fournir des informations pronostiques importantes aux professionnels de la santé. Dans cette étude observationnelle prospective d'un an, nous avons examiné l'association entre les scores au Short Performance Physical Battery (SPPB), d'une part, et les consultations à l'urgence et les hospitalisations au cours de l'étude, d'autre part. Au total, 191 patients ayant été nouvellement référés à une clinique gériatrique externe de Hamilton (Ontario) ont été contactés, et parmi eux, 120 pris part à l'étude. Le SPPB et d'autres évaluations ont été réalisés dans le cadre de consultations de routine. Les dossiers médicaux électroniques ont été examinés pour déterminer le nombre de consultations à l'urgence et d'hospitalisations dans l'année qui a suivi l'évaluation de base. Des analyses de régression logistique ont été utilisées pour identifier des prédicteurs des consultations à l'urgence et des hospitalisations. Le score moyen au SPPB dans la cohorte étudiée (moyenne d'âge = 80,6 ans, écart-type = 6,3 ans ; 53 % de femmes) était de 6,3 (écart-type = 3,2). Au cours de cette période d'un an, le score au SPPB était associé au nombre de consultations à l'urgence [RR = 0,90 (0,78-1,03)] et d'hospitalisations [RR = 0,84 (0,72-0,97)], après ajustement pour l'âge, le sexe et les comorbidités.Tools applied at the point of care can provide valuable prognostic information for practitioners. In this one-year, prospective observational study, we examined the association of the short performance physical battery (SPPB) and one-year emergency department (ED) visits and hospitalizations. Overall, 191 new referrals attending an outpatient geriatric clinic in Hamilton, Ontario, were approached, and 120 were enrolled. SPPB and other assessments were completed during the routine clinical visit. ED visits and hospitalizations within one year of the baseline assessment were abstracted from electronic medical records. Logistic regression analyses were used to determine ED visits and hospitalization predictors. The mean SPPB score in the study cohort (mean age 80.6, SD 6.3 years; 53% female) was 6.3 (SD 3.2). SPPB score was associated with a one-year ED visit (OR = 0.90 [0.78­1.03]) and hospitalization (OR = 0.84 [0.72­0.97]) after adjusting for age, sex, and co-morbidities.

Prevalence of osteoporosis in osteoarthritic patients undergoing total hip or total knee arthroplasty.

OBJECTIVE: To determine the prevalence of osteoporosis in osteoarthritic patients undergoing total hip or total knee arthroplasty. DESIGN: Cross-sectional study. SETTING: The Specialized Outpatient Rehabilitation Service's (SORS) Pre-surgical Arthroplasty Service located at the Chedoke Hospital, Hamilton Health Sciences, Hamilton, ON, Canada. PARTICIPANTS: SORS outpatients (N=364), from the period of March 2006 to March 2007. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Prevalence of osteoporosis was determined by review of a self-reported survey, and defined by (1) self-reported diagnosis of osteoporosis, (2) history of fragility fracture (defined by a bone fracture occurring as a result of a fall from standing height or less after the age of 50), or (3) current treatment for osteoporosis using bisphosphonates. RESULTS: Of the study cohort, 26% were classified as having osteoporosis, according to our criteria. Of the patients with self-reported osteoporosis or a history of fragility fractures, only 37% and 17% reported current treatment with bisphosphonates, respectively. CONCLUSIONS: Osteoporosis is common in the osteoarthritic arthroplasty population, with a prevalence at least equal to that in the general population. Due to the self-reported nature of the study, the prevalence of osteoporosis in this population is likely significantly higher. Results from this study indicate need for further research, specifically in formal assessment for osteoporosis in patients undergoing a joint replacement.

The Relationship between Intramuscular Adipose Tissue, Functional Mobility, and Strength in Postmenopausal Women with and without Type 2 Diabetes.

Objectives. To determine (1) whether intramuscular adipose tissue (IntraMAT) differs between women with and without type 2 diabetes and (2) the association between IntraMAT and mobility and strength. Methods. 59 women ≥ 65 years with and without type 2 diabetes were included. A 1-Tesla MRI was used to acquire images of the leg. Timed-up-and-go (TUG) and grip strength were measured. Regression was used to determine associations between the following: (1) type 2 diabetes and IntraMAT (covariates: age, ethnicity, BMI, waist : hip ratio, and energy expenditure), (2) IntraMAT and TUG (covariates: diabetes, age, BMI, and energy expenditure), and (3) IntraMAT and grip strength (covariates: diabetes, age, height, and lean mass). Results. Women with diabetes had more IntraMAT. After adjustment, IntraMAT was similar between groups (diabetes mean [SD] = 13.2 [1.4]%, controls 11.8 [1.3]%, P = 0.515). IntraMAT was related to TUG and grip strength, but the relationships became nonsignificant after adjustment for covariates (difference/percent IntraMAT [95% CI]: TUG = 0.041 seconds [-0.079-0.161], P = 0.498, grip strength = -0.144 kg [-0.335-0.066], P = 0.175). Conclusions. IntraMAT alone may not be a clinically important predictor of functional mobility and strength; however, whether losses in functional mobility and strength are promoted by IntraMAT accumulation should be explored.

Association of larger holes in the trabecular bone at the distal radius in postmenopausal women with type 2 diabetes mellitus compared to controls.

OBJECTIVE: Adults with type 2 diabetes mellitus (DM) have an elevated fracture risk despite normal areal bone mineral density (aBMD). The study objective was to compare trabecular bone microarchitecture of postmenopausal women with type 2 DM and women without type 2 DM. METHODS: An extremity 1T magnetic resonance imaging system was used to acquire axial images (195 × 195 × 1,000 µm(3) voxel size) of the distal radius of women recruited from outpatient clinics or by community advertisement. Image segmentation yielded geometric, topologic, and stereologic outcomes, i.e., number and size of trabecular bone network holes (marrow spaces), endosteal area, trabecular bone volume fraction, nodal and branch density, and apparent trabecular thickness, separation, and number. Lumbar spine (LS) and proximal femur BMD were measured with dual x-ray absorptiometry. Microarchitectural differences were assessed using linear regression and adjusted for percent body fat, ethnicity, timed up-and-go test, Charlson Index, and calcium and vitamin D intake; aBMD differences were adjusted for body mass index (BMI). RESULTS: Women with type 2 DM (n = 30, mean ± SD age 71.0 ± 4.8 years) had larger holes (+13.3%; P = 0.001) within the trabecular bone network than women without type 2 DM (n = 30, mean ± SD age 70.7 ± 4.9 years). LS aBMD was greater in women with type 2 DM; however, after adjustment for BMI, LS aBMD did not differ between groups. CONCLUSION: In women with type 2 DM, the average hole size within the trabecular bone network at the distal radius is greater compared to controls. This may explain the elevated fracture risk in this population.

A food frequency questionnaire for the assessment of calcium, vitamin D and vitamin K: a pilot validation study.

The study objective was to validate a food frequency questionnaire (FFQ) to assess calcium, vitamin D and vitamin K intakes in overweight and obese postmenopausal community-dwelling women. The FFQ was validated against intakes derived from a 5-day diet record (5DDR) that also included assessment of supplement intake. Strong correlations between methods were observed for all nutrients (r = 0.63, 0.89, 0.54 for calcium, vitamin D and vitamin K, respectively) and cross-classification analyses demonstrated no major misclassification of participants into intake quartiles. Bland-Altman analysis showed that the FFQ overestimated intakes for calcium, by 576 mg/day (95% CI, -668 to 1,821 mg/day), for vitamin D by 75 IU/day (95% CI, -359 to 510 IU/day), and for vitamin K by 167 mcg/day (95% CI, -233 to 568 mcg/day). This pilot study showed promising validation evidence for the use of this FFQ, which focuses on calcium, vitamin D and vitamin K intakes in postmenopausal women, as a screening tool in clinical and research settings.

One-year weight maintenance after significant weight loss in healthy overweight and obese subjects: does diet composition matter?

BACKGROUND: For many people, maintenance of weight loss is elusive. Whereas high-protein (HP) diets have been found to be superior to high-carbohydrate (HC) diets for weight loss in the short term, their benefits long term are unclear, particularly for weight maintenance. Furthermore, the literature lacks consensus on the long-term effects of an HP diet on cardiovascular disease risk factors. OBJECTIVE: The objective was to investigate whether macronutrient dietary composition plays a role in weight maintenance and in improvement of cardiovascular disease risk factors. DESIGN: The study comprised 2 phases. Phase 1 featured a very-low-energy diet for 3 mo. In phase 2, the subjects were randomly assigned to an HP or an HC diet for 12 mo. The diets were isocaloric, tightly controlled, and individually prescribed for weight maintenance. The subjects were overweight or obese but otherwise healthy men and women. RESULTS: The subjects lost an average of 16.5 kg during phase 1 and maintained a mean (+/-SEM) weight loss of 14.5 +/- 1.2 kg (P < 0.001) during phase 2; no significant differences between groups were observed. By the end of the study, reductions in systolic blood pressure were 14.3 +/- 2.4 mm Hg for the HP group and 7.7 +/- 2.2 mm Hg for the HC group (P < 0.045). Forty-seven percent of the 180 subjects who began the study completed both phases. CONCLUSIONS: The results indicate that the protein or carbohydrate content of the diet has no effect on successful weight-loss maintenance. A general linear model analysis indicated that dietary treatment (HP or HC) was a significant factor in systolic blood pressure change and in favor of the HP diet. This trial was registered at www.clinicaltrials.gov as NCT 00625236.

Adiponectin resistance precedes the accumulation of skeletal muscle lipids and insulin resistance in high-fat-fed rats.

High-fat (HF) diets can induce insulin resistance (IR) by altering skeletal muscle lipid metabolism. An imbalance between fatty acid (FA) uptake and oxidation results in intramuscular lipid accumulation, which can impair the insulin-signaling cascade. Adiponectin (Ad) is an insulin-sensitizing adipokine known to stimulate skeletal muscle FA oxidation and reduce lipid accumulation. Evidence of Ad resistance has been shown in obesity and following chronic HF feeding and may contribute to lipid accumulation observed in these conditions. Whether Ad resistance precedes and is associated with the development of IR is unknown. We conducted a time course HF feeding trial for 3 days, 2 wk, or 4 wk to determine the onset of Ad resistance and identify the ensuing changes in lipid metabolism and insulin signaling leading to IR in skeletal muscle. Ad stimulated FA oxidation (+28%, P < or = 0.05) and acetyl-CoA carboxylase phosphorylation (+34%, P < or = 0.05) in control animals but failed to do so in any HF-fed group (i.e., as early as 3 days). By 2 wk, plasma membrane FA transporters and intramuscular diacylglycerol (DAG) and ceramide were increased, and insulin-stimulated phosphorylation of both protein kinase B and protein kinase B substrate 160 was blunted compared with control animals. After 4 wk of HF feeding, maximal insulin-stimulated glucose transport was impaired compared with control. Taken together, our results demonstrate that an early loss of Ad's stimulatory effect on FA oxidation precedes an increase in plasmalemmal FA transporters and the accumulation of intramuscular DAG and ceramide, blunted insulin signaling, and ultimately impaired maximal insulin-stimulated glucose transport in skeletal muscle induced by HF diets.