Approximately one in three adults 65 years and older fall each year and these falls lead to a substantial number of serious injuries and deaths. Numerous interventions have been proposed for fall-prevention but the efficacy can vary, and may be due to the general nature of the interventions. Older adults may be able to improve their ability to recover from a postural perturbation through perturbation-based balance training (PBBT), similar to the way other motor skills can be improved through training. The purpose of the first study was to investigate the effects of age and fall risk on the efficacy of PBBT. Participants (young adults, older adults at low-risk of falling, older adults at high-risk of falling) completed PBBT on a moving platform three times a week for one month. Balance was quantified using the time to stabilization of the COP and normalized to platform displacement (nTTS), where a decrease in nTTS can be interpreted as an improvement in balance. A significant main effect of group revealed high-risk fallers had a significantly higher nTTS than young adults and a significant main effect of session revealed nTTS was significantly lower one week and one month post-training than before training. The purpose of the second study was to investigate the effect of training amount on the efficacy of PBBT in older adults. Ten healthy older adults completed PBBT either three times a week or five times a week for four weeks. Both training amounts were sufficient for significant improvements in nTTS one week after training. However, training five times a week was necessary for older adults to maintain improvements in nTTS one month post training. The purpose of the third study was to investigate the need for PBBT after strength training in order to improve balance in older adults. A torque-driven, three-segment, musculoskeletal model and forward dynamic simulations were used to address the hypothesis. Increasing joint strength was beneficial in recovering balance from a postural perturbation only after re-optimization of the torque activation. These results provide support for supplementing strength training fall prevention interventions in older adults with task-related practice. / Ph. D.

Title: Selected exercise trends and its effect on trunk stabilization function in dialysed patients - overview of the literature. Objective: Objective of this diploma thesis was to obtain and compare available studies dealing with exercise trends such as yoga, pilates, tai chi and balance training devices and to evaluate their effect on musculature which participates on trunk stabilization system of dialysed patients. Methods: This diploma thesis has descriptively-analytical character and is structured in a form of literary review. Results: Issue of dialysis in connection with trunk stabilization system has not been sufficiently explored yet in literary sources.In conclusion, there were no studies found dealing with effects of particular exercise trends on spine stabilization system of dialysed patients.In order to comprehend this issue an overview was written to define the effect of such trends on dialysed patients. Also, complications arising from renal failure and dialysis were mentioned such as hypertension, diabetes melitus and obesity.The effect of these trends on trunk stabilization system of healthy population as well as patients suffering from chronic back pain was described too. Conclusion: Some extent of coherence was found between strengthening musculature which plays an important role...

It is well established that aging is associated with numerous health concerns, including poor balance. Deteriorations in attention demand also place older adults at a greater risk for falls. Emerging experiments have explored the impact of dual-task training programs and have improved dual-tasking in older adults. However, it is unknown whether these performance-related improvements are a function of the intervention itself or the repeated exposure to the testing protocol. Study 1 explored the implications of repeated administration, once per week for 5 weeks, of a protocol involving standing postural sway while concurrently performing reaction time (RT) tasks in older adults. Results revealed that postural sway was stable across testing sessions whereas the difficult RT task gradually improved over time. Study 2 examined the influence of repeated exposure, once per week for 5 weeks, of a protocol involving negotiating a series of obstacles while performing RT tasks in older adults. Participants walked significantly faster with repeated exposure and gradually improved RT. Study 3 investigated the impact of repeated exposure, once per week for 5 weeks, to three functional mobility measures in older adults. It also examined the influence of a 12-week balance and mobility training (BMT) program as well as a 12-week balance and mobility plus cognitive training (BMT+C) program on functional mobility in older adults. Functional mobility served to be stable over time. Both the BMT and BMT+C groups significantly improved functional mobility and sustained these improvements at the 12-week follow-up, while no changes were observed in the control group. No differences between the BMT and BMT+C groups emerged. Experiment 4 examined the influence of BMT and BMT+C on postural sway and RT in older adults. Participants in both training groups significantly improved RT and sustained these improvements at the follow-up, while no changes were observed in the control group. No changes to postural control were shown in any group. No differences between the BMT and BMT+C groups emerged. Experiment 5 examined the influence of BMT and BMT+C on negotiating a series of obstacles while performing RT tasks in older adults. Both the BMT and BMT+C groups significantly improved RT and sustained these improvements at the follow-up, while no changes were observed in the control group. All groups showed faster time to completion of the obstacle series. No differences between the BMT and BMT+C groups emerged. Collectively, these findings suggest that BMT and BMT+C significantly improve functional mobility and divided attention, and sustain these improvements over time. Although some improvements were observed after repeated exposure over 5 weeks, no changes in the control group were observed. Therefore, the improvements exhibited from BMT and BMT+C are likely not a function of repeated exposure to the testing protocol, as participants may be more susceptible to performance-related improvements when the testing sessions are close in proximity. Altogether, these findings propose that, whether or not cognitive training is included, attention demanding dual-task training not only improves functional mobility and RT, but also sustains these improvements over time in older adults. These results may be used to improve the prescription of exercise in older adults.

The present thesis deals with the issue of balance disorders in patients with multiple sclerosis (MS) and the effect of individual balance training using biofeedback. It presents an overview of the current knowledge about MS - epidemiology, pathogenesis, diagnostics, types, symptoms and treatment methods. The thesis also describes principles of balance control of the human body, balance deficits in patients with MS and physiotherapeutic treatment. The aim of the experimental part was to evaluate the effect of the Homebalance® system on balance in MS patients and its comparison with conventionally used sensorimotor training. A total of 18 people took part in the research, 9 in the experimental group and 9 in the control group. Standardized tests and functional scales supplemented by standardized questionnaires on balance and gait were used to objectively assess balance. Measurements were performed before and after a series of therapies. After treatment, a significant improvement (p 0,05) was found in some tests and functional scales, but in none of subjective patient reported outcomes. Exercise using the Homebalance® system may be a suitable alternative to classical rehabilitation methods used for balance training in people with MS. Keywords Multiple sclerosis, balance impairment, Homebalance®,...

Context: Individuals with chronic ankle instability (CAI) rely more on visual information during postural control due to impaired proprioceptive function. The increased reliance on visual information may increase the risk of injury when their vision is limited during complex sports activities. Stroboscopic glasses may help elicit sensory reweighting during postural control. Therefore, we assumed that the glasses would induce and train CAI patients to reweight sensory information for the somatosensory system during dynamic balance training. Purpose: (1) to identify the effects of the 4-week dynamic balance training on the reliance of visual information during postural control in patients with CAI and (2) to compare the effects of the 4-week dynamic balance with and without stroboscopic glasses on postural control in patients with CAI. Methods: This study was a randomized controlled trial. Twenty-eight CAI patients were equally assigned to one of 2 groups: a strobe group (6 males and 8 females) or a control group (8 males and 6 females). The 4-week dynamic balance training consisted of multiple single-legged exercises. The strobe group wore stroboscopic glasses during the training, but the control group did not. The main outcome measures included the following: self-reported function measures, static postural control (center of posture (COP)-based measures), and dynamic postural control including the Dynamic Postural Stability Index (DPSI), and the Star Excursion Balance Test (SEBT). There were 3 visual conditions in the static postural control (eyes-open (EO), strobe vision (SV), and eyes-closed (EC)), and 2 conditions in the dynamic postural control (EO and SV). Two-way randomized block ANOVAs were used to assess changes in postural control in each group and condition by using pretest-posttest mean differences. Results: The strobe group showed a higher difference in COP velocity in medial-lateral direction (VelML) and vertical stability index (VSI) under the SV condition compared with the control group (p = .005 and .004, respectively). In addition, the strobe group had significant decreases in VelML, DPSI, and VSI at the posttest compared with the pretest (p = .0001, .01, and .005, respectively). Conclusion: The 4-week dynamic balance training with stroboscopic glasses appeared to be effective in improving postural control and altering visual reliance in patients with CAI.

Trip-induced falls are a leading cause of injuries among adults aged 65 years or older. Perturbation-based balance training (PBT) has emerged as an exercise-based fall prevention intervention and shown efficacy in reducing the risk of trip-induced falls. The broad goal of my PhD research was to advance the application of this so-called trip training through three studies designed to address existing knowledge gaps. First, trip training is commonly conducted with the aid of costly specialized treadmills to induce trip-like perturbations. An alternative version of trip training that eliminates the need for a treadmill would enhance training feasibility and enable wider adoption. The goal of the first study was to compare the effects of non-treadmill training (NT), treadmill training (TT), and a control (i.e., no training) on reactive balance after laboratory-induced trips among community-dwelling older adults. After three weeks of the assigned intervention, participants were exposed to two laboratory-induced trips while walking. Results showed different beneficial effects of NT and TT. For example, NT may be more beneficial in improving recovery step kinematics, while TT may be more beneficial in improving trunk kinematics, compared to the control. While the first study showed the effects of PBT on laboratory-induced trips, little is known about how such training affects responses to real-world trips. Responses to real-world trips may be captured using wearable inertial measurement units (IMUs), yet IMUs have not been adequately validated for this use. Therefore, the goal of the second study was to investigate the concurrent validity of IMU-based trunk kinematics against the gold standard optical motion capture (OMC)-based trunk kinematics after overground trips among community-dwelling older adults. During two laboratory-induced trips, participants wore two IMUs placed on the sternum and shoulder, and OMC markers placed at anatomical landmarks of the trunk segment. Results showed that IMU-based trunk kinematics differed between falls and recoveries after overground trips, and exhibited at least good correlation (Pearson's correlation coefficient, r > 0.5) with the gold standard OMC-based trunk kinematics. The goal of the third study was then to explore differences in tripping kinematics between the laboratory and real world using wearable IMUs among community-dwelling older adults. Participants were asked to wear three IMUs (for sternum and both feet) and a voice recorder to capture their responses to real-world losses of balance (LOBs) during their daily activities for three weeks. Results showed a higher variance in laboratory-induced trips than real-world trips, and the study demonstrated the feasibility of using IMUs and a voice recorder to understand the underlying mechanisms and context of real-world LOBs. Overall, this work was innovative by evaluating a non-treadmill version of trip training, establishing the validity of IMUs in capturing kinematic responses after overground trips, and applying IMUs and a voice recorder to assess tripping kinematics in the real world. The results from this work will advance the use of PBT to reduce the prevalence of trip-induced falls and to investigate the real-world effects of such trip training in future studies. / Doctor of Philosophy / Trips and falls are a major health problem especially among older adults who are aged 65 years or older. Researchers have developed an innovative exercise-based fall prevention training program, which has shown to be helpful in reducing trips and falls. The broad goal of my PhD research was to advance the use of this so-called trip training through three new research studies. First, specialized treadmills are commonly used for trip training to simulate trip-induced falls. An alternative version of trip training without a treadmill would allow more people to receive benefits from this training. The goal of the first study was to compare the effects of non-treadmill training (NT), treadmill training (TT), and no training on balance recovery after tripping in the laboratory. Older adults living in the local community were recruited as research participants and completed NT, TT, or no training over three weeks. After that, they attended a laboratory session where they were tripped twice while walking on a walkway. Results showed that NT helped to take a longer and faster recovery step, while TT helped to limit trunk forward bending during tripping, both of which are important movements to prevent falling after tripping. While the first study showed benefits of trip training in the laboratory, not much is known about the benefits of trip training in the real world. Wearable sensors called inertial measurement units can record body movements without laboratory motion capture cameras, but their ability to record dynamic body movements during tripping needs to be tested. The goal of the second study was to evaluate the capabilities of these wearable sensors on recording trunk movements during tripping and compare them to those recorded by laboratory motion capture cameras. Participants were tripped twice in the laboratory, and their trunk movements were recorded by several wearable sensors and laboratory motion capture cameras. Results showed that these wearable sensors can distinguish between fallers and non-fallers after tripping, and that the trunk movements recorded by the wearable sensors were associated with those recorded by the laboratory motion capture cameras. With this confirmation, the third study was designed to compare balance recovery after tripping between the laboratory and real world using wearable sensors. Participants were asked to wear three wearable sensors and a voice recorder during their daily activities for three weeks. The wearable sensors recorded their trunk and feet movements, while the voice recorder was used for participants to provide detailed explanations of balance losses they experienced. Results showed a higher variability in balance recovery from the laboratory trips compared to the real-world trips. In addition, this study demonstrated that wearable sensors and a voice recorder can be used to study how people reacted to a balance loss and what they did to recover (or fall) from it. Overall, my PhD research work suggested a new version of trip training that does not require a treadmill, proved that wearable sensors can be used to record important body movements during tripping, and demonstrated the method to study balance recovery responses in the real world using wearable sensors. The results from the three studies will promote the use of trip training and provide guidelines for evaluating benefits of trip training in the real world.

Slips, trips, and falls are a serious public health concern, particularly among older adults and within occupational settings, given that falls contribute to a large number of injuries and associate with high medical costs. To reduce the number of falls, there is a need to better understand risk factors contributing to falls, and to develop and evaluate improved balance training interventions to prevent falls. To address these needs, this work has two primary goals: first, to better understand risk factors contributing to falls, including fatigue and balance reactions after a large postural perturbation, and, second, to develop and evaluate improved reactive balance training (RBT) interventions to reduce risk of falls due to slipping and tripping. The first study investigated the effects of performing occupationally-relevant fatigue-inducing physical work on trip and fall risk. Healthy young adults performed a simulated manual material handling (MMH) task, using either heavy or light boxes, for two hours. Gait measures related to risk of tripping and slipping were assessed before and after the task. Reactive balance during one laboratory-induced trip was also assessed after the task. Results showed that performing the heavy MMH task did not affect risk of tripping or slipping, or reactive balance after tripping. These results may have resulted from insufficient fatigue due to the MMH task. The second study investigated the relationship between feet kinematics upon slipping while walking, and the outcome of the slip. Seventy-one laboratory-induced slips were analyzed, which included recoveries, feet-split falls, feet-forward falls, and lateral falls. Feet kinematics differed between these four slip outcomes, and a discriminant model including six measures of feet kinematics correctly predicted 87% of slip outcomes. Two potentially modifiable characteristics of feet kinematics upon slipping that can improve the likelihood of successfully averting a fall were identified: (1) quickly arresting the motion of the slipping foot; and (2) a recovery step that places the trailing toe approximately 0-10% body height anterior to the sacrum. This information may be used to guide the development of improved RBT interventions to reduce risk of slip-induced falls. The third study evaluated the efficacy of two low-cost, low-tech RBT methods for improving reactive balance after slipping. The two methods were: unexpected slip training (UST), which involved repeated unexpected slips while walking and volitional slip-recovery training (VST), which involved practicing balance reactions after volitionally inducing a slip-like perturbation. Young adults completed one session of an assigned intervention (UST, VST, or control), followed by one unexpected, laboratory-induced slip while walking. Compared to controls, UST and VST resulted in a higher proportion of successful balance recoveries from the laboratory-induced slips. UST improved both proactive control and reactive stepping after slipping, while VST primarily improved the ability to arrest slipping foot motion. These results support the use of UST and VST as practical, low-tech methods of slip training. The fourth study evaluated the efficacy of RBT that targets both slipping and tripping. Community-dwelling, healthy older adults (61-75 years) completed four sessions of either RBT (treadmill-based trip-recovery training and VST) or control training (general strength and balance exercises). Reactive balance during unexpected laboratory-induced slips and trips was assessed before and after RBT, and compared between subjects at baseline (before the intervention), after control training, and after RBT. The incidence of slip-induced falls differed between groups in that 80% fell at baseline, 60% fell after control training, and 18% fell after RBT. Post-RBT subjects also exhibited less severe slips, compared to baseline and post-control subjects. The incidence of trip-induced falls did not differ between groups, but margin of stability after tripping was greater for post-RBT subjects, compared to post-control subjects. These results show promise for the use of RBT applied to both slipping and tripping to reduce fall risk among older adults. / Doctor of Philosophy / Slips, trips, and falls are a serious public health concern, given that falls contribute to a large number of injuries and deaths. Falls are particularly concerning among older adults, who are reported to fall more frequently, and within occupational settings, where falls cause a larger number of injuries and a significant economic burden. To reduce the number of falls, there is a need to better understand risk factors contributing to falls, and to develop and evaluate improved balance training interventions to prevent falls. Four studies were conducted to address these needs: two studies aimed to better understand risk factors contributing to falls, including fatigue and balance reactions after slipping, and two studies aimed to develop and evaluate improved balance training interventions to reduce risk of falls due to slipping and tripping. This work focused on slipping and tripping, because slips and trips are reported to cause a large number of injuries and falls among both workers and older adults. The first study investigated the effect of performing occupationally-relevant fatigue-inducing physical work on trip and fall risk among healthy young adults, and results showed that performing a simulated manual material handling task (i.e. moving and stacking boxes using a two-wheeled dolly) did not affect risk of tripping and falling. The second study investigated the relationship between balance reactions after slipping and the outcome of the slip. Results showed that balance reactions of the feet predicted the outcome of the slip (i.e. recovering balance or one of three types of slip-induced falls) with 87% accuracy. We also identified characteristics of balance reactions that can improve the likelihood of successfully averting a fall. The third study evaluated the efficacy of two low-tech reactive balance training (RBT) methods for reducing slip-induced fall risk among young adults. These methods involved practicing balance reactions after slip-like perturbations, induced either unexpectedly or volitionally. Results showed that both RBT methods improved reactive balance after slipping, but through different mechanisms. The fourth study evaluated the efficacy of a RBT intervention targeting both slipping and tripping among older adults. Results showed that RBT improved reactive balance during both slipping and tripping, and reduced the incidence of slip-induced falls. In conclusion, these results help to better understand risk factors contributing to falls, and support the use of practical reactive balance training interventions targeting both slipping and tripping to reduce fall risk.

Title: The effect of selected exercise trends activating core stability system in dialysed patients - overview of the literature. Objective: Objective of this diploma thesis was to obtain and compare available studies dealing with exercise trends such as yoga, pilates, tai chi and balance training devices and to evaluate their effect on core stability system of dialysed patients. Methods: This diploma thesis has descriptively-analytical character and is structured in a form of literary review. Results: Issue of dialysis in connection with core stability system has not been sufficiently explored yet in literary sources. In conclusion, there were no studies found dealing with effects of particular exercise trends on core stability system of dialysed patients. In order to comprehend this issue an overview was written to define the effect of such trends on dialysed patients. Also, complications arising from renal failure and dialysis were mentioned such as hypertension, diabetes melitus and obesity. The effect of these trends on core stability system of healthy population as well as patients suffering from chronic back pain was described too. Conclusion: Some extent of coherence was found between strengthening core stability system and its effect on dialysed patients however further in- depth research...

Thesis title: The effect of kinesthetic sensation on the postural control and balance abilities of individuals with visual impairments Objectives: Compose through the literature study appropriete balance programe for the individuals with visual impairments and measure its effect on their postural control and balance abilities. Methods: Ten visually impaired subjects, one subject with visual and vestibular impairment and one healthy subject took part in this study. Movement intervention was held once a week for eleven weeks, consisting of balance and coordination training, exercises for decreasing muscle imbalances and increasing body awareness and relaxation ability. The Footscan system was used for measuring the effect of movement intervention on the on the postural control and balance abilities of individuals with visual impairments. The testing was done before the beginning and after the finishing of all classes of movement intervention and the results of the pretest and posttest were compared with each other. Results: The movement intervention led to the improvement of postural control and balance abilities at five subjects from the total of nine subjects, who underwent pre and post testing. From the total of forty-eight carried out tests, the subjects noted improvement in twenty-two tests,...

This thesis is based on studies of the ten-year community-based intervention programme entitled, the Vadstena Osteoporosis Prevention Project (VOPP). The specific aims of the research were to describe the effects of physical activity and training programmes on bone mass and balance performance in adults, to determine whether a fall risk prevention programme could motivate personal actions among the elderly, to ascertain whether the intervention programme could reduce the incidence of forearm and hip fractures. Two studies addressed training programmes for middle-aged and old people. First, VOPP participants who were aged 40–70 years and had low forearm bone mineral density (BMD) values were invited to take part in a one-year weight-bearing training study. Thirty of those individuals were included in the investigation. Additional bone mass measurements were performed at the hip and the lumbar spine, and balance and aerobic capacity were also tested. The training programme was performed twice a week (I). In the second study, healthy persons aged 70–75 years were invited to participate in a balance-training study. Fifteen persons joined an exercise group, and another fifteen were controls. The training programme comprised specific balance exercises and was carried out twice a week for nine weeks (II). The association between forearm BMD values and several lifestyle factors was explored in random samples of the population aged 20–72 years (n=880) in a cross-sectional study (III). Another study explored the association between calcaneal stiffness, forearm BMD, and lifestyle factors amongst participants aged 20–79 years (n=956) at the final registration of the VOPP (V). Effects of the VOPP interventions directed at environmental risk factors for falls and the promotion of physical activity were examined in people aged ≥ 65 years (IV). The incidence of forearm and hip fractures was studied amongst middle-aged and elderly individuals in the intervention and the control communities during the study period 1987–2001 (VI). The exercise group (n=15) in the weight-bearing training study showed increases in BMD at the greater trochanter (p<0.01), one-leg stance balance with the eyes closed and coordination tests (p<0.05), and aerobic capacity (p<0.05). No significant difference was found when the groups were compared concerning changes in the different tests during the intervention period (I). In the balance-training study, the exercise group showed post-training improvement in the following tests: standing on the right leg with eyes closed (p<0.01), standing on the right leg (p<0.01) and on the left leg (p<0.05) while turning the head, and walking 30 metres (p<0.01). There were significant differences between the groups in these tests when changes were compared at the post-intervention test (II). Age (p<0.0001) and body mass index (p≤.0001) were associated with forearm BMD in both sexes. Reported moderate physical activity levels in men were positively associated with forearm BMD (p<0.05) (III). In both sexes, reported moderate (p<0.05) and high (women p<0.05 and men p<0.001) physical activity levels were positively associated with calcaneal stiffness. The correlation coefficient between forearm BMD and calcaneal stiffness was 0.58 in women and 0.34 in men (V). Persons aged ≥ 65 years at the follow-up in 1994 reported more use of shoe/cane spikes and moderate physical activity levels compared to controls (IV). There was no change in the general incidence of forearm and hip fractures between the communities for the study period. However, there was a tendency towards decreasing incidence of forearm and trochanteric hip fracture in both sexes during the late intervention period in the intervention community (VI). A community-based intervention programme aimed at reducing the incidence of osteoporotic fractures must be regarded as a long-term project and should preferably be monitored over an extended post-intervention period. / On the day of the public defence the statuses of articles IV and V were Submitted and VI was Manuscript