OBJECTIVE -The aim of this study was to investigate the effect of shoe design on the plantar pressure dynamics of patients with diabetic neuropathy during walking.RESEARCH DESIGN AND METHODS -Three shoe design categories were tested. Total contact area and biomechanical variables in multiple areas under the foot were measured.RESULTS -Shoes with a rocker bottom principle reduced pressure 35-65% underneath the heel and the central metatarsal heads. Increased contact area did not result in significant pressure reductions underneath the forefoot. Pressure dynamics underneath the heel and medial forefoot (first metatarsal head and hallux) on average showed no significant differences among the different shoes with a cushioning insole.CONCLUSIONS -The most effective way to offload the forefoot of patients with neuropathic feet is through the use of the rocker sole principle. In general, the effect of an insole depends on the design characteristics of a shoe. Predicting the effect of therapeutic footwear on an individual scale, however, remains difficult. Therefore, in-shoe pressure measurements seem to be necessary to evaluate a therapeutic shoe prescription in certain individual cases. Diabetes Care 26:441-445, 2003B auman et al. (1) were among the first researchers who published their study on the relationship between high-pressure areas and plantar ulceration in the insensitive foot. They appreciated the effect of both a total contact cast and certain orthopedic shoes on the healing process of neuropathic ulcers. They investigated the effect of shoe sole design on plantar pressure reduction using small pressure sensors taped to specific areas underneath the sole of the foot.Using similar equipment 25 years later, Nawoczenski et al. (2) showed that certain pivotal and curved rocker bottom shoes were able to effectively reduce forefoot pressure in normal subjects. Many studies have followed since then (rev. in 3). However, despite all the pioneering work, different disciplines dealing with the neuropathic foot often still disagree about which therapeutic shoe modalities to prescribe. In the Netherlands, also, this is a continuing topic of dispute. Although some strongly propagate the use of custom made (orthopedic) shoes with a stiff sole and rocker bar to prevent recurrence of a neuropathic ulcer, others recommend the use of an extra depth shoe. It has been argued that these less heavy, more cosmetically attractive shoes would be at least as effective in preventing recurrence of neuropathic ulcers.According to Spencer, "There is a need to measure the effectiveness of the range of pressure relieving interventions for the prevention and treatment of diabetic foot ulcers as there is a small amount of poor quality research in this area" (3). The present study was performed to investigate the relation between shoe design and pressure reduction in the context of the above discussion. Three shoe design categories were tested. Total contact area and biomechanical variables in multiple areas under the foot were measured usin...

Objective: Several lines of evidence support a potential role of skeletal muscle mitochondrial dysfunction in the pathogenesis of insulin resistance and/or type 2 diabetes. However, it remains to be established whether mitochondrial dysfunction represents either cause or consequence of the disease. We examined in vivo skeletal muscle mitochondrial function in early and advanced stages of type 2 diabetes, with the aim to gain insight in the proposed role of mitochondrial dysfunction in the aetiology of insulin resistance and/or type 2 diabetes. Methods: Ten long-standing, insulin-treated type 2 diabetes patients, 11 subjects with impaired fasting glucose, impaired glucose tolerance and/or recently diagnosed type 2 diabetes, and 12 healthy, normoglycaemic controls, matched for age and body composition and with low habitual physical activity levels were studied. In vivo mitochondrial function of the vastus lateralis muscle was evaluated from post-exercise phosphocreatine (PCr) recovery kinetics using 31 P magnetic resonance spectroscopy (MRS). Intramyocellular lipid (IMCL) content was assessed in the same muscle using single-voxel 1 H MRS. Results: IMCL content tended to be higher in the type 2 diabetes patients when compared with normoglycaemic controls (PZ0.06). The 31 P MRS parameters for mitochondrial function, i.e. PCr and ADP recovery time constants and maximum aerobic capacity, did not differ between groups. Conclusions: The finding that in vivo skeletal muscle oxidative capacity does not differ between longstanding, insulin-treated type 2 diabetes patients, subjects with early stage type 2 diabetes and sedentary, normoglycaemic controls suggests that mitochondrial dysfunction does not necessarily represent either cause or consequence of insulin resistance and/or type 2 diabetes.European Journal of Endocrinology 158 643-653

Life-long regular endurance exercise is known to counteract the deterioration of cardiovascular and metabolic function and overall mortality. Yet it remains unknown if life-long regular endurance exercise can influence the connective tissue accumulation of advanced glycation endproducts (AGEs) that is associated with aging and lifestyle-related diseases. We therefore examined two groups of healthy elderly men: 15 master athletes (64±4 years) who had been engaged in life-long endurance running and 12 old untrained (66±4 years) together with two groups of healthy young men; ten young athletes matched for running distance (26±4 years), and 12 young untrained (24±3 years). AGE cross-links (pentosidine) of the patellar tendon AGE (2014) were measured biochemically, and in the skin, it was assessed by a fluorometric method. In addition, we determined mechanical properties and microstructure of the patellar tendon. Life-long regular endurance runners (master athletes) had a 21 % lower AGE cross-link density compared to old untrained. Furthermore, both master athletes and young athletes displayed a thicker patellar tendon. These cross-sectional data suggest that life-long regular endurance running can partly counteract the aging process in connective tissue by reducing age-related accumulation of AGEs. This may not only benefit skin and tendon but also other long-lived protein tissues in the body. Furthermore, it appears that endurance running yields tendon tissue hypertrophy that may serve to lower the stress on the tendon and thereby reduce the risk of injury.

Other than diet and medication, exercise is considered one of the three cornerstones of good diabetes treatment. Nevertheless, current clinical guidelines on Type 2 diabetes provide no detailed information on the modalities of effective exercise intervention in the treatment of Type 2 diabetes. Based on a review of currently available literature, exercise modalities are being identified to maximize the benefits of exercise intervention in the treatment of different Type 2 diabetes subpopulations. Both endurance and resistance types of exercise have equal therapeutic strength to improve metabolic control in patients with Type 2 diabetes. When applying endurance-type exercise, energy expenditure should be equivalent to approximately 1.7-2.1 MJ/exercise bout on 3 but preferably 5 days/wk. In sarcopenic or severely deconditioned patients with Type 2 diabetes, focus should lie on the implementation of resistance-type exercise to attenuate and/or reverse the decline in skeletal muscle mass and strength. Before choosing the most appropriate exercise modalities, the patient's disease stage should be well characterized, and an ECG-stress test should be considered. Based on baseline aerobic fitness, level of co-morbidities, body composition, and muscle strength, patients should be provided with an individually tailored exercise intervention program to optimize therapeutic value. A multidisciplinary individualized approach and continued exercise training under personal supervision is essential to enhance compliance and allow long-term health benefits of an exercise intervention program.

Aims/hypothesis The 5′-AMP-activated protein kinase (AMPK) pathway is intact in type 2 diabetic patients and is seen as a target for diabetes treatment. In this study, we aimed to assess the impact of the AMPK activator 5-aminoimidazole-4-carboxamide riboside (AICAR) on both glucose and fatty acid metabolism in vivo in type 2 diabetic patients.Methods Stable isotope methodology and blood and muscle biopsy sampling were applied to assess blood glucose and fatty acid kinetics following continuous i.v. infusion of AICAR (0.75 mg kg −1 min −1 ) and/or NaCl (0.9%) in ten male type 2 diabetic patients (age 64±2 years; BMI 28±1 kg/m 2 ). Results Plasma glucose rate of appearance (R a ) was reduced following AICAR administration, while plasma glucose rate of disappearance (R d ) was similar in the AICAR and control test. Consequently, blood glucose disposal (R d expressed as a percentage of R a ) was increased following AICAR infusion (p<0.001). Accordingly, a greater decline in plasma glucose concentration was observed following AICAR infusion (p<0.001). Plasma NEFA R a and R d were both significantly reduced in response to AICAR infusion, and were accompanied by a significant decline in plasma NEFA concentration. Although AMPK phosphorylation in skeletal muscle was not increased, we observed a significant increase in acetyl-CoA carboxylase phosphorylation (p<0.001). Conclusions/interpretation The i.v. administration of AICAR reduces hepatic glucose output, thereby lowering blood glucose concentrations in vivo in type 2 diabetic patients. Furthermore, AICAR administration stimulates hepatic fatty acid oxidation and/or inhibits whole body lipolysis, thereby reducing plasma NEFA concentration.

This study assesses femoral neck shortening and its effect on gait pattern and muscle strength in patients with femoral neck fractures treated with internal fixation. Seventy-six patients from a multicenter randomized controlled trial participated. Patient characteristics and Short Form 12 and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were collected. Femoral neck shortening, gait parameters, and maximum isometric forces of the hip muscles were measured and differences between the fractured and contralateral leg were calculated. Variables of patients with little or no shortening, moderate shortening, and severe shortening were compared using univariate and multivariate analyses. Median femoral neck shortening was 1.1 cm. Subtle changes in gait pattern, reduced gait velocity, and reduced abductor muscle strength were observed. Age, weight, and Pauwels classification were risk factors for femoral neck shortening. Femoral neck shortening decreased gait velocity and seemed to impair gait symmetry and physical functioning. In conclusion, internal fixation of femoral neck fractures results in permanent physical limitations. The relatively young and healthy patients in our study seem capable of compensating. Attention should be paid to femoral neck shortening and proper correction with a heel lift, as inadequate correction may cause physical complaints and influence outcome.

Aims/hypothesis Structured exercise is considered a cornerstone in type 2 diabetes treatment. However, adherence to combined resistance and endurance type exercise or medical fitness intervention programmes is generally poor. Groupbased brisk walking may represent an attractive alternative, but its long-term efficacy as compared with an individualised approach such as medical fitness intervention programmes is unknown. We compared the clinical benefits of a 12-month exercise intervention programme consisting of either brisk walking or a medical fitness programme in type 2 diabetes patients. Methods We randomised 92 type 2 diabetes patients (60± 9 years old) to either three times a week of 60 min brisk walking (n=49) or medical fitness programme (n=43). Primary outcome was the difference in changes in HbA 1c values at 12 months. Secondary outcomes were differences in changes in blood pressure, plasma lipid concentrations, insulin sensitivity, body composition, physical fitness, programme adherence rate and health-related quality of life. Results After 12 months, 18 brisk walking and 19 medical fitness participants were still actively participating. In both programmes, 50 and 25% of the dropout was attributed to overuse injuries and lack of motivation, respectively. Intention-to-treat analyses showed no important differences between brisk walking and medical fitness programme in primary or secondary outcome variables. Conclusions/interpretation The prescription of group-based brisk walking represents an equally effective intervention to modulate glycaemic control and cardiovascular risk profile in type 2 diabetes patients when compared with more individualised medical fitness programmes. Future exercise intervention programmes should anticipate the high attrition rate due to overuse injuries and motivation problems.

Structured exercise is considered an important cornerstone to achieve good glycemic control and improve cardiovascular risk profile in Type 2 diabetes. Current clinical guidelines acknowledge the therapeutic strength of exercise intervention. This paper reviews the wide pathophysiological problems associated with Type 2 diabetes and discusses the benefits of exercise therapy on phenotype characteristics, glycemic control and cardiovascular risk profile in Type 2 diabetes patients. Based on the currently available literature, it is concluded that Type 2 diabetes patients should be stimulated to participate in specifically designed exercise intervention programs. More attention should be paid to cardiovascular and musculoskeletal deconditioning as well as motivational factors to improve long-term treatment adherence and clinical efficacy. More clinical research is warranted to establish the efficacy of exercise intervention in a more differentiated approach for Type 2 diabetes subpopulations within different stages of the disease and various levels of co-morbidity.