Effects of local heating and whole-body hyperthermia on neuromuscular and cognitive function in young and old healthy adults / ; Vietinio šildymo ir viso kūno hipertermijos poveikis jaunų ir pagyvenusių sveikų suaugusiųjų nervų-raumenų ir kognityvinėms funkcijoms.

More than one-fifth (21.1%) of the European Union (EU) population was aged 65 and over in 2022(Population Structure and Ageing, 2022) and its proration in the EU and worldwide is expected to increase rapidly in coming years (Shimizu et al., 2020).What’s more, one-third of people aged 65 years and older fall each year, and this number reaches 46% in those aged 85 years and older (Blake et al., 1988; A. D. Smith et al., 2010).Among those who fall, 50% do so repeatedly (Tinetti et al., 1988).A progressive decline in neuromuscular function, characterized by a structural decline in the number (Lexell et al., 1983) and size (Trappe et al., 2003) of muscle fibers and a decrease in neuron fiber size and density (Wang et al., 1999), directly contributes to the overall loss of muscle mass and strength in older adults. Functionally, loss of muscle strength and decline in neural function are associated with the increased incidence of falls observed in the elderly population; therefore, these falls are associated with significant mobility impairment (Evans & Campbell, 1993), disability (Guralnik & Simonsick, 1993), and a consequent loss of independence and quality of life. Because of the age-related loss of active muscle mass and consequent reduction in the basal and resting metabolicrate (Brazaitis et al., 2017; Fleg & Lakatta, 1988; Poehlman et al., 1994), the temperature of the skin and deep muscles (at ~ 3.5 cm) of the lower extremities decreases in older (64–80 years) adults compared with younger (19– 21 years)adults, by about 1.32 °C and 1.33 °C, respectively (Brazaitis et al., 2019).Physiologically, the conduction velocity of nerves decreases or increases at a speed rate of1.1–2.4 m/s/°C (Abramson et al., 1966; Denys, 1991; Gassel & Trojaborg, 1964; Halar et al., 1983).This suggests that, in addition to the age-related decline in neuromuscular structural, morphological, and functional properties (Hunter et al., 2016), the decrease in body temperature can profoundly change motor function and performance ...