| 1. |
- Elhadi, Mustafa M. O., et al.
(författare)
-
Comprehensive gait analysis of healthy older adults who have undergone long-distance walking
- 2017
-
Ingår i: Journal of Aging and Physical Activity. - : Human Kinetics. - 1063-8652 .- 1543-267X. ; 25:3, s. 367-377
-
Tidskriftsartikel (refereegranskat)abstract
- Many older adults do not adhere to the recommended physical activity levels. This study examines the gait changes upon longdistance walking among healthy older adults. Gait tests of 24 adults aged 65 or more were conducted at baseline and at the end of 30 and 60min of treadmill walking. Spatial temporal, kinematic, and kinetic gait data were computed. Perceived level of exertion was evaluated for each subject. Ten subjects (group B) perceived higher exertion levels than the remaining 14 subjects (group A). After walking, group B had significant reductions in dominant-side ankle joint range of motion and power, suggesting lower-leg muscle fatigue, which appeared to be compensated by significantly increased nondominant-side knee and hip motions. These changes were not observed in group A. Differences in gait parameters between groups A and B implied that some biomechanical factors might contribute to the lack of walking of some older adults.
|
|
| 2. |
- Hampton, Stephanie E., et al.
(författare)
-
Ecology under lake ice
- 2017
-
Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 20:1, s. 98-111
-
Forskningsöversikt (refereegranskat)abstract
- Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experience periods of snow and ice cover. Relatively little is known of winter ecology in these systems, due to a historical research focus on summer ‘growing seasons’. We executed the first global quantitative synthesis on under-ice lake ecology, including 36 abiotic and biotic variables from 42 research groups and 101 lakes, examining seasonal differences and connections as well as how seasonal differences vary with geophysical factors. Plankton were more abundant under ice than expected; mean winter values were 43.2% of summer values for chlorophyll a, 15.8% of summer phytoplankton biovolume and 25.3% of summer zooplankton density. Dissolved nitrogen concentrations were typically higher during winter, and these differences were exaggerated in smaller lakes. Lake size also influenced winter-summer patterns for dissolved organic carbon (DOC), with higher winter DOC in smaller lakes. At coarse levels of taxonomic aggregation, phytoplankton and zooplankton community composition showed few systematic differences between seasons, although literature suggests that seasonal differences are frequently lake-specific, species-specific, or occur at the level of functional group. Within the subset of lakes that had longer time series, winter influenced the subsequent summer for some nutrient variables and zooplankton biomass.
|
|
| 3. |
- Ma, Christina Zong-Hao, et al.
(författare)
-
A vibrotactile and plantar force measurement-based biofeedback system : Paving the way towards wearable balance-improving devices
- 2015
-
Ingår i: Sensors. - : MDPI. - 1424-8220. ; 15:12, s. 31709-31722
-
Tidskriftsartikel (refereegranskat)abstract
- Although biofeedback systems have been used to improve balance with success, they were confined to hospital training applications. Little attempt has been made to investigate the use of in-shoe plantar force measurement and wireless technology to turn hospital training biofeedback systems into wearable devices. This research developed a wearable biofeedback system which detects body sway by analyzing the plantar force and provides users with the corresponding haptic cues. The effects of this system were evaluated in thirty young and elderly subjects with simulated reduced foot sensation. Subjects performed a Romberg test under three conditions: (1) no socks, system turned-off; (2) wearing five layers of socks, system turned-off; (3) wearing five layers of socks, and system turned-on. Degree of body sway was investigated by computing the center of pressure (COP) movement measured by a floor-mounted force platform. Plantar tactile sensation was evaluated using a monofilament test. Wearing multiple socks significantly decreased the plantar tactile sensory input (p < 0.05), and increased the COP parameters (p < 0.017), indicating increased postural sway. After turning on the biofeedback system, the COP parameters decreased significantly (p < 0.017). The positive results of this study should inspire future development of wearable plantar force-based biofeedback systems for improving balance in people with sensory deficits.
|
|
| 4. |
- Ma, Christina Zong-Hao, et al.
(författare)
-
Balance improvement effects of biofeedback systems with state-of-the-art wearable sensors : A systematic review
- 2016
-
Ingår i: Sensors. - : MDPI. - 1424-8220. ; 16:4
-
Forskningsöversikt (refereegranskat)abstract
- Falls and fall-induced injuries are major global public health problems. Balance and gait disorders have been the second leading cause of falls. Inertial motion sensors and force sensors have been widely used to monitor both static and dynamic balance performance. Based on the detected performance, instant visual, auditory, electrotactile and vibrotactile biofeedback could be provided to augment the somatosensory input and enhance balance control. This review aims to synthesize the research examining the effect of biofeedback systems, with wearable inertial motion sensors and force sensors, on balance performance. Randomized and non-randomized clinical trials were included in this review. All studies were evaluated based on the methodological quality. Sample characteristics, device design and study characteristics were summarized. Most previous studies suggested that biofeedback devices were effective in enhancing static and dynamic balance in healthy young and older adults, and patients with balance and gait disorders. Attention should be paid to the choice of appropriate types of sensors and biofeedback for different intended purposes. Maximizing the computing capacity of the micro-processer, while minimizing the size of the electronic components, appears to be the future direction of optimizing the devices. Wearable balance-improving devices have their potential of serving as balance aids in daily life, which can be used indoors and outdoors.
|
|
| 5. |
- Ma, Christina Zong-Hao, et al.
(författare)
-
Effects of orthopedic insoles on static balance of older adults wearing thick socks
- 2018
-
Ingår i: Prosthetics and Orthotics International. - : Sage Publications. - 0309-3646 .- 1746-1553. ; 42:3, s. 357-362
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The wearing of socks and insoles may affect the ability of the foot to detect tactile input influencing postural balance.Objectives: The aim of this study was to investigate whether (1) thick socks adversely affected the elderly postural balance and (2) orthopedic insoles could improve the elderly postural balance while wearing thick socks.Study design: Repeated-measures study design. Methods: In total, 14 healthy older adults were recruited. A monofilament test was conducted to evaluate foot plantar sensation with and without thick socks. Subjects then performed the Romberg tests under three conditions: (1) barefoot, (2) with socks only, and (3) with both socks and insoles. Postural balance was assessed by measuring the center of pressure movement during standing in each experimental condition.Results: Thick socks significantly decreased the monofilament score (p < 0.001), suggesting reduction in ability to detect external forces. All center of pressure parameters increased significantly while wearing thick socks (p < 0.017), implying reduction of postural stability. They then decreased significantly with the additional use of insoles (p < 0.017).Conclusion: Previous studies have documented the changes in plantar pressure distribution with the use of orthopedic insoles. This study further suggests that such changes in contact mechanics could produce some balance-improving effects, which appears not to have been reported earlier.Clinical relevance: Wearing thick socks reduces plantar pressure sensitivity and increases postural sway which may increase risk of falls. Orthopedic insoles and footwear with similar design could potentially be a cost-effective method in maintaining postural balance when wearing thick socks.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Wan, Anson H., et al.
(författare)
-
Wearable vibrotactile biofeedback device allowing identification of different floor conditions for lower-limb amputees
- 2016
-
Ingår i: Archives of Physical Medicine and Rehabilitation. - : Elsevier. - 0003-9993 .- 1532-821X. ; 97:7, s. 1210-1213
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To evaluate a newly developed biofeedback device enabling lower-limb amputees to identify various floor conditions.Design: Self-control with repeated measures (with and without the biofeedback device) within the amputee group, and group control comparing between amputee and nonamputee groups.Setting: University locomotion laboratory.Participants: Five lower-limb amputees and 8 nonamputees (N=13).Interventions: A wearable biofeedback device, which identified different floor conditions by analyzing the force patterns under the prosthetic feet and provided vibration cues in response to different floor conditions, was provided to the amputees.Main Outcome Measures: The subjects stepped on a foam platform concealing a small object or no object at 1 of the 4 locations of the foot sole. Subjects were asked whether there was a small object under their feet and the location of the object if it existed. The test was repeated with 4 different object types and 4 object locations. The success rate of floor identification was evaluated.Results: Without the biofeedback device, nonamputee subjects (76.56%) identified floor conditions better than amputees (22.5%) significantly (P<.001). On using the biofeedback device, the amputees significantly improved (P<.01) their success rate showing no significant difference (P=.746) compared with the nonamputees. No significant differences were found among object types (P=.689).Conclusions: Amputees performed significantly worse than nonamputees in recognizing the different floor conditions used in this experiment. With the biofeedback device, amputees significantly improved their abilities in identifying different floor conditions. Future attempts could configure the device to allow it to provide warning signals in response to fall-inducing conditions.
|
|
