Clinical Research Directory

Sleep Apnea in Elderly

Sleep-disordered breathing (SDB or sleep apnea) is very common among elderly Veterans and leads to increased morbidity and mortality in this population. The proposal aims to identity whether oxygen, finasteride and acetazolamide can be effective in reducing unstable breathing and eliminating sleep apnea in the elderly via different mechanisms. This proposal will enhance the investigators' understanding of the pathways that contribute to the development of sleep apnea in the elderly. The investigators expect that the results obtained from this study will positively impact the health of Veterans by identifying new treatment modalities for sleep apnea. A cumulative effect of the investigators' research will fulfill the long-term goal of improving the quality of life of elderly Veterans suffering from sleep apnea and its potential life-threatening complications.

Effects of Eccentric Training at Long Muscle Length on Functional Capacities of Elderly Adults

As aging leads to a decline in muscle function and overall physical performance, interventions targeting muscle strength and neuromechanical properties are critical for maintaining functional independence in older adults. Long-length eccentric training has shown promise in enhancing muscle performance, but its effects in older adults, particularly in a home-based setting, remain underexplored. The aim of this trial is to assess whether a targeted home-based training intervention incorporating long-length eccentric contractions can enhance functional capacity and neuromechanical properties in healthy older adults. Participants will be semi-randomly allocated to one of two groups: an experimental group incorporating long-length eccentric contractions (Group 1) or a conventional resistance training group (Group 2), with group assignment stratified to ensure an equal number of men and women in each group. Each participant will complete three laboratory-based experimental sessions (i.e., two Pre-training sessions and one Post-training session) , during which five key evaluations will be conducted: (i) the 5-Time Sit to Stand test, serving as the primary outcome measure; (ii) the Timed Up and Go test; (iii) assessments of isometric and dynamic muscle strength in the knee extensors and plantar flexors; (iv) measurements of the cross-sectional areas of the vastus lateralis, rectus femoris, gastrocnemius medialis, and soleus muscles; and (v) evaluation of tendon stiffness. Following the pre-evaluation, each participant will engage in a 24-session, semi-supervised, home-based training protocol over a period of 8 to 11 weeks. The training program will include eight exercises, with four targeting the upper limbs and four focused on the lower limbs. Group 1 will perform the lower limb exercises at long muscle lengths, while Group 2 will perform the same exercises in a conventional manner (i.e., at neutral or shorter muscle lengths). The total training volume (calculated as repetitions × sets, in arbitrary units) will be matched across both groups, ensuring that any observed differences in outcomes are attributable to the specific training modality rather than differences in workload.