The increase in the proportion of elderly people in the population is one of the most remarkable sociodemographic phenomena of the twenty-first century. The number of patients with diabetes is also increasing worldwide with this demographic change. Given these facts, consideration of the problems the general elderly population is facing in the management of diabetes is essential. In this review article, we focus on sarcopenia, which is the decrease in lower extremity muscle mass and muscle strength accompanying aging, describe the relationship between sarcopenia and diabetes, and highlight the specific factors through which diabetes contributes to loss of muscle strength. The quantitative methods for evaluating lower extremity muscle strength will also be described. These methods hold the key to assessing the effectiveness of exercise therapy and optimizing the assessment of the degree of autonomy in the activities of daily living. Exercise is one of the basic treatments for type 2 diabetes and may also prevent and improve sarcopenia. This review discusses the aspects common to the two health conditions and elucidates the effectiveness and necessity of exercise as a preventive measure against diabetes among the elderly.

Cough peak flow (CPF) is a measurement for evaluating the risk of cough dysfunction and can be measured using various devices, such as spirometers. However, complex device setup and the face mask required to be firmly attached to the mouth impose burdens on both patients and their caregivers. Therefore, this study develops a novel cough strength evaluation method using cough sounds. This paper presents an exponential model to estimate CPF from the cough peak sound pressure level (CPSL). We investigated the relationship between cough sounds and cough flows and the effects of a measurement condition of cough sound, microphone type and participant’s height and gender on CPF estimation accuracy. The results confirmed that the proposed model estimated CPF with a high accuracy. The absolute error between CPFs and estimated CPFs were significantly lower when the microphone distance from the participant’s mouth was within 30 cm than when the distance exceeded 30 cm. Analysis of the model parameters showed that the estimation accuracy was not affected by participant’s height or gender. These results indicate that the proposed model has the potential to improve the feasibility of measuring and assessing CPF.

Although cough peak flow (CPF) is an important measurement for evaluating the risk of cough dysfunction, some patients cannot use conventional measurement instruments, such as spirometers, because of the configurational burden of the instruments. Therefore, we previously developed a cough strength estimation method using cough sounds based on a simple acoustic and aerodynamic model. However, the previous model did not consider age or have a user interface for practical application. This study clarifies the cough strength prediction accuracy using an improved model in young and elderly participants. Additionally, a user interface for mobile devices was developed to record cough sounds and estimate cough strength using the proposed method. We then performed experiments on 33 young participants (21.3 ± 0.4 years) and 25 elderly participants (80.4 ± 6.1 years) to test the effect of age on the CPF estimation accuracy. The percentage error between the measured and estimated CPFs was approximately 6.19%. In addition, among the elderly participants, the current model improved the estimation accuracy of the previous model by a percentage error of approximately 6.5% (p < 0.001). Furthermore, Bland-Altman analysis demonstrated no systematic error between the measured and estimated CPFs. These results suggest that the developed device can be applied for daily CPF measurements in clinical practice.

Patients with type 2 diabetes may have motor dysfunctions such as loss of muscle strength. Compared with non-diabetic subjects, patients with diabetes show decreased lower extremity muscle strength. The aim of this review was to describe the influence of factors associated with loss of muscle strength in patients with type 2 diabetes. Aging promotes an accelerated loss of muscle strength in patients with diabetes. Physical inactivity may cause a decline in muscle strength in patients with diabetes. Gradual loss of muscle strength is related to the presence and severity of diabetic neuropathy. Diabetic nephropathy may be a factor contributing to loss of muscle strength, because decrease in skeletal muscle mass is a hallmark of end-stage renal disease. Resistance exercise is an essential component of diabetes treatment regimens and also plays a role in the prevention and management of sarcopenia. Intensive physical therapy intervention should be provided to patients with diabetes having decreased muscle strength.

Anti-gravity treadmill training has the potential to support the prosthetic rehabilitation of below-knee amputees, especially for patients whose physical strength and vitality are decreased.