## 4 Discussion  
This study aimed to evaluate the influence of HoF and FoF on spatiotemporal parameters, including task velocity and time; single- and double-support times; peak downward CoM velocity; and kinematic parameters, such as, hip, knee, and ankle angles, as well as FC and FP with respect to older adults during stair descents and gait transitions. At baseline, the participants exhibited similar characteristics regarding age, gender, health conditions, and prescribed medication, as well as physical activity conditions and functional mobility. However, regarding BMI, cognitive conditions, and ADL performance, the participants exhibited different characteristics. The probability of falling increases with age [2; 5], and the previous literature has reported that one third of the community-dwelling  
population aged 60 and over experiences at least one fall per year [6,9]. The participants who exhibited HoF in our study corroborate these findings. Gender differences in stair negotiation were previously reported, showing that women present a higher risk of falling and a higher prevalence of falls on stairs [10]. The female ratio in the participants with HoF in our study supports these findings. Excessive body weight has been reported to contribute to a reduction in the ability to perform ADLs, such as stair negotiation, and therefore, it has been associated with falls in older adults [43]. Accordingly, the current study shows that older adults with FoF are more likely to fall due to the significantly higher BMI when compared to older adults without FoF. Polypharmacy has been reported to be one of the major factors in the risk of falling [2,7] to the extent that there is a specific category of medications denominated as \"Fall-Risk-Increasing Drugs\" (FRIDs). FRIDs can influence the risk of falling by adversely affecting the cardiovascular or central nervous systems [44]. The participants with HoF in our study corroborate these findings, presenting a combination of prescribed medications that can be considered FRIDs. To the best of our knowledge, an HGS cut-off that predicts the risk of falling has not been determined; however, the loss of muscle mass and strength has been established as an important risk factor for falls [45]. Comparing our results to the data provided by [PERSON] et al., who established that the average HGS for older Portuguese adults was 30.3 Kg among men and 18 Kg among women [46], it is possible to assume that our participants presented reasonable HGS. Regarding spatiotemporal parameters, in line with previous reports, our results showed that older adults with HoF and FoF adopt conservative strategies, descending stairs slower and more cautiously to avoid falling [8]. It has been stated that the gait velocity is the most consistent change associated with age, diminishing 1% per year from the age of 60 onwards, being responsible for a 7% increase in falls [17]. Accordingly, [PERSON] et al. also reported that older adults descend stairs more slowly [20]. Our results support these findings, with both HoF and FoF groups presenting reduced task velocity and time. This may indicate that older adults use a more conservative and cautious strategy to maintain dynamic balance to prevent falls [37]. The previous literature has found that at level gait and during stair descent, older adults show increased double-support time [2,20], which may be the result of a weaker swing limb advancement because of muscle power loss, as well as decreased trunk and lower-limb stability [17]. This also indicates that older adults may require more time after the limb advancement to maintain weight-bearing stability [37]. Accordingly, [PERSON] et al. found that at level gait, older adults with HoF exhibit increased double-support time [37]; however, in our study, only older adults with FoF presented longer double-support time when compared to older adults without FoF. The results of the current study also demonstrate that participants with HoF and FoF present decreased peak downward CoM velocity.