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This section presents information on articles related to adapted physical activity. The articles include "Learning through outdoor adventure education," found in an issue of "Teaching Exceptional Children," "Hemispheric specialization and implications for the education of the hearing impaired," found in an issue of "American Annals of the Deaf," and "Modification of spastic gait through mechanical damping," found in an issue of the "Journal of Biomechanics."

Background: One of the more pervasive effects of aging is loss of cutaneous sensation, which appears to correlate with impaired postural control and increased risk of falling. This study examined the potential for compensating for the destabilizing effects of reduced cutaneous sensitivity by placing a raised edge underneath the perimeter of the plantar foot surface, so as to facilitate sensation from the stability boundaries of the base of support.Methods: The main experiment involved 14 healthy older adults (aged 65-73) selected because they were known, from a previous study, to have moderate plantar cutaneous insensitivity. We also report results of an initial experiment involving 7 healthy young adults (aged 23-31). In both experiments, we studied effects of the plantar facilitation on control of rapid stepping reactions evoked by unpredictable postural perturbation, applied via sudden platform movement in forward, backward, and lateral directions. We also studied effects on "feet-in-place" responses evoked by continuous pseudorandom platform motion in mediolateral and anteroposterior directions. Subjects were blindfolded in all tests.Results: Plantar facilitation reduced the incidence of "extra" limb movements, beyond the initial step, during forward-step reactions in the older adults. There also appeared to be an improved ability to control feet-in-place reactions: young subjects were better able to recover balance without stepping when falling backward (given instructions to "try not to step"), and both young and older subjects reduced the extent to which the center of foot pressure approached the posterior foot boundary during continuous anteroposterior platform motion.Conclusions: This study provides evidence that mechanical facilitation of sensation from the boundaries of the plantar surface of the foot can improve the efficacy of certain types of stabilizing reactions evoked by unpredictable postural perturbation. The results may be directly transferable to the design of special footwear insoles to reduce instability and risk of falling in older adults. [ABSTRACT FROM AUTHOR]

Background: Recent studies highlight the importance of compensatory stepping to preserve stability, and the spatial and temporal demands placed on the control of this reaction. Age-related changes in the control of stepping could greatly influence the risk of falling. The present study compares, in healthy elderly and young adults, the characteristics of compensatory stepping responses to unpredictable postural perturbations.Methods: A moving platform was used to unpredictably perturb the upright stance of 14 naive, active and mobile subjects (5 aged 22 to 28 and 9 aged 65 to 81). The first 10 randomized trials (5 forward and 5 backward) were evaluated to allow a focus on reactions to relatively novel perturbations. The behavior of the subjects was not constrained. Forceplate and kinematic measures were used to evaluate the responses evoked by the brief (600 msec) platform translation.Results: Subjects stepped in 98% of the trials. Although the elderly were less likely to execute a lateral anticipatory postural adjustment prior to foot-lift, the onset of swing-leg unloading tended to begin at the same time in the two age groups. There was remarkable similarity between the young and elderly in many other characteristics of the first step of the response. In spite of this similarity, the elderly subjects were twice as likely to take additional steps to regain stability (63% of trials for elderly). Moreover, in elderly subjects, the additional steps were often directed so as to preserve lateral stability, whereas the young rarely showed this tendency.Conclusions: Given the functional significance of base-of-support changes as a strategy for preserving stability and the age-related differences presently revealed, assessment of the capacity to preserve stability against unpredictable perturbation, and specific measures such as the occurrence or placement of multiple steps, may prove to be a significant predictor of falling risk and an important outcome in evaluating or developing intervention strategies to prevent falls. [ABSTRACT FROM AUTHOR]

Postural perturbations are often used in experimental investigations of human balance and postural control. Treating the perturbation as the input and the resulting postural sway response as the output, an input/output model of the posture-control system can be identified. Selection of the perturbation parameters can have a substantial influence on the accuracy of the identification and on the interpretation of the results. Pertinent parameters include type of perturbation, waveform, power spectrum, bandwidth, amplitude and test duration. The selection of these parameters is discussed in the light of general requirements for persistent excitation, accurate identification, stationarity and subject safety. Experimental results are used to illustrate specific issues. [ABSTRACT FROM AUTHOR]

Background: This study compares several psychological indicators of balance confidence in relation to physical performance, past and current experience, gender bias, and other perceptions of daily functioning.Methods: Sixty community-dwelling ambulatory elders (aged 65-95) were administered the Falls Efficacy Scale (FES), the Activities-Specific Balance Confidence Scale (ABC), and three dichotomous questions on fear of falling, activity avoidance, and perceived need for personal assistance to ambulate outdoors. Performance measures on walking (average speed) and balance (static posturography) were obtained on a subsample of 21 subjects.Results: Balance confidence assessed by the ABC and self-perceived need for personal assistance with outdoor ambulation were the only indicators significantly associated with the performance measures. As expected, perceived balance capabilities were more strongly related to current behavior (frequency of doing specific activities) than to past experience (fall history). Gender differences in self-report emerged for the global fear-of-falling indicator but not for the two efficacy ratings.Conclusions: Psychological indicators of balance confidence are important to measure both in conjunction with balance test performance and as a legitimate focus of rehabilitation. Of the various indicators assessed here, the dichotomous fear-of-falling question appears to have the least utility. Perceived need for personal assistance to ambulate outdoors has merit as an initial clinical screening question for discriminating persons on the basis of both physical ability and confidence. The ABC scale appears to have the greatest utility as an evaluative index for older persons at a moderate to high level of functioning. [ABSTRACT FROM AUTHOR]

Background: Lateral falls are common in older adults and are associated with an elevated risk of hip fracture, compared with falls in other directions. Although rapid stepping movements can play an important functional role in maintaining balance, control of lateral stepping is a complex and demanding motor task. This study examined whether there are age-related differences in the stepping behavior used to recover from lateral loss of balance.Methods: Rapid stepping reactions were evoked in healthy, active young (aged 20-30 years; N = 10) and older (aged 65-73 years; N = 10) volunteers by means of a sudden unpredictable motion of a platform on which the subject either stood quietly or walked in place. Subjects were instructed to respond naturally. Video analysis was performed to characterize the patterns of limb movement evoked by lateral platform motion.Results: In responding to lateral perturbation of stance, the older adults were much more likely than the young adults to take multiple steps or use arm reactions to regain equilibrium, particularly when attempting crossover steps. During walk-in-place trials, both young and older subjects more frequently used a sequence of side steps rather than crossovers; however, older adults were still more likely to take extra steps or use arm reactions. Collisions between swing foot and stance limb occurred in 55% of walk-in-place trials in older adults versus only 8% in young adults.Conclusions: Control of lateral-stepping reactions appears to create difficulties for active and healthy older adults above and beyond previously reported problems in controlling forward and backward stepping. Impaired control of lateral-stepping reactions may be an early indicator of increased risk for lateral falls and hip fracture and should be an important consideration in the development of clinical approaches to predicting and preventing falls and related injuries. [ABSTRACT FROM AUTHOR]