Mechanisms of Slowed Foot Tap Speed in Older Adults

Rapid repetitive tapping, like the Foot Tap Test (FTT), slows with age, but the underlying mechanisms are unknown. Purpose: 1. Test the hypotheses that greater performance variability, increased muscle coactivation, and slowed muscle contractile speeds are related to lower foot tap count (FTC) in older adults; 2. Examine the relationship between FTC and physical function in older adults, using the advanced SPPB-A. Methods: 18 (25.0±3.1years, 9F, mean±SD), and 28 (73.4±4.9, 14F) adults were recruited; the later were divided into Higher (HFO) and Lower (LFO) Functioning based on SPPB-A score. Participants performed 10s of rapid tapping (FTT) while seated. A MATLAB program was used to calculate FTC and variability of the intertap-interval (COV-ITI). Contractile speed (rates of force development and relaxation, RFD and RFR) of the dorsiflexor muscles were determined using ballistic contractions. Electromyography was recorded on the tibialis anterior, soleus, and coactivation was calculated based on their agreement. Results: LFO had a lower FTC than Young and HFO (45.9±7.0taps, 54.4±7.5, 53.1±5.7, respectively; p=0.003), and lower COV-ITI than Young (12.3±5.9%, 20.5±8.1, respectively, p=0.009). No associations were found between COV-ITI and FTC. Coactivation was higher in Young than HFO (0.568±0.209, 0.321±0.129) and was negatively related to FTC in older (r2=0.274, p=0.005). The LFO had a slower RFD than Young and FTC was positively related to maximal RFD (r2=0.345, p=0.001) and RFR (r2=0.162, p=0.038) in older adults. In older, FTC was related to SPPB-A (r2=0.329, p=0.001). Conclusions: Greater coactivation during the FTT and slower force development may negatively affect FTC in older adults

The 3rd International Conference on the Challenges, Opportunities, Innovations and Applications in Electronic Textiles

This reprint is a collection of papers from the E-Textiles 2021 Conference and represents the state-of-the-art from both academia and industry in the development of smart fabrics that incorporate electronic and sensing functionality. The reprint presents a wide range of applications of the technology including wearable textile devices for healthcare applications such as respiratory monitoring and functional electrical stimulation. Manufacturing approaches include printed smart materials, knitted e-textiles and flexible electronic circuit assembly within fabrics and garments. E-textile sustainability, a key future requirement for the technology, is also considered. Supplying power is a constant challenge for all wireless wearable technologies and the collection includes papers on triboelectric energy harvesting and textile-based water-activated batteries. Finally, the application of textiles antennas in both sensing and 5G wireless communications is demonstrated, where different antenna designs and their response to stimuli are presented

Biomechanical effects of patellar taping in subjects with patellofemoral pain syndrome (PFPS).

PhDPatellofemoral pain syndrome (PFPS) is one of the most common musculoskeletal disorders affecting adults. Patellar taping provides an effective treatment in alleviating the symptoms of a high proportion of subjects who present with PFPS. However, the mechanisms of pain reduction have not been established. The aim of this work was to evaluate the effects of patellar taping on the biomechanics of the patellofemoral joint and level of pain in PFPS subjects, during the eccentric phase of single leg squatting at 30° of knee flexion. These were determined with a combined kinetic and kinematic approach using data from video analysis, force plate and EMG. A series of pilot tests was performed, involving a group of asymptomatic volunteers performing a number of knee flexion procedures. These tests demonstrated a high reliability in both the estimated patellofemoral joint reaction force (PFJRF) and relative amplitude of vasti, but less impressive reliability for the parameters associated with muscle onset. The main case-controlled study involved 18 PFPS subjects, recruited from a local Physiotherapy Department, and a similar number of healthy controls. The test procedure was performed on the knees of both subject groups and, where appropriate, during and after patellar taping. The results revealed that the mean value of PFJRF, which was 2025 N prior to taping, had decreased significantly to 1720 N (p< 0.05) following a period of taping and exercises which lasted between 2-5 weeks. Equivalent changes were also recorded with the pain levels, although the ratio of the amplitude of the vasti did not change during this period. The only significant differences between the two subject groups were with the relative timing of muscle onset, for which VMO preceded VL in the healthy controls. The reduction of biomechanical characteristics following the application of patellar tape and exercises in PFPS subjects, may explain the mechanism of pain reduction during the early phase of single leg squatting