Dale A. Ulrich

Effects of Intensity of Treadmill Training on Developmental Outcomes and Stepping in Infants With Down Syndrome : A Randomized Trial

Background and Purpose: Infants with Down syndrome (DS) are consistently late walkers. The purpose of this investigation was to test the effects of individualized, progressively more intense treadmill training on developmental outcomes in infants with DS. Subjects: Thirty infants born with DS were randomly assigned to receive lower-intensity, generalized treadmill training or higher-intensity, individualized training implemented by their parents in their homes. Methods: Research staff members monitored implementation of training, physical growth, and onset of motor milestones of all infants on a monthly basis. Results: Infants in the higher-intensity, individualized training group increased their stepping more dramatically over the course of training. Infants in the higher-intensity training group attained most of the motor milestones at an earlier mean age. Discussion and Conclusion: Treadmill training of infants with DS is an excellent supplement to regularly scheduled physical therapy intervention for the purpose of reducing the delay in the onset of walking.

Estimating Measurement Validity: A Tutorial

The purposes of this tutorial are threefold: (a) to clarify the meaning of measurement validity, (b) to provide appropriate validation procedures for use by researchers in adapted physical activity, and (c) to raise the awareness of the limitations of the traditional views on measurement validity. Several validation procedures are described with specific examples from adapted physical activity research based on traditional approaches of providing validity evidence. Conceptual and empirical limitations of the traditional validity framework are discussed. We recommend that several categories of validity evidence should be reported in research studies. We encourage practicing the unified concept of measurement validity (Messick, 1993, 1995) in adapted physical activity research and practice.

The physical activity patterns of children with autism

BackgroundAlthough motor deficits are gaining attention in autism research much less attention has been paid to the physical activity patterns in this group of children. The participants in this study were a group of children with autism spectrum disorder (N = 72) between the ages of 9-18 years. This cross-sectional study explored the physical activity patterns of seventy-two children with autism spectrum disorder as they aged.FindingsResults indicated significant differences between the mean time spent in moderate to vigorous physical activity and the mean time spent in sedentary activity. Older children with autism spectrum disorder are significantly more physically inactive, compared to younger children.ConclusionsPhysical activity programs and interventions need to address this deficit, in physical activity. Children with autism have a similar trend in physical activity patterns compared to their peers without autism; associated benefits and future research will be discussed.

Exploring effects of different treadmill interventions on walking onset and gait patterns in infants with Down syndrome.

Two cohorts of participants were included to investigate the effects of different treadmill interventions on walking onset and gait patterns in infants with Down syndrome (DS). The first cohort included 30 infants with DS (17 males, 13 females; mean age 10mo [SD 1.9mo]) who were randomly assigned to either a lower‐intensity‐generalized (LG) training group, or a higher‐intensity‐individualized (HI) training group. A control (C) group from another study, who did not receive treadmill training, served as the control (eight males, seven females; mean age 10.4mo [SD 2.2mo]). Mean age at walking onset was 19.2, 21.4, and 23.9 months for the HI, LG, and C groups respectively. At walking onset the HI group was significantly younger than the C group (p=0.011). At the gait follow‐up that was conducted between 1 and 3 months after walking onset, three groups significantly different in overall gait patterns (p=0.037) were examined by six basic gait parameters including average velocity, stride length, step width, stride time, stance time, and dynamic base. Post‐hoc analyses demonstrated that stride length was the gait parameter largely contributing to this overall group difference (p=0.033), and the HI group produced a significantly longer stride length than the C group (p=0.030). In conclusion, the HI treadmill intervention significantly promoted earlier walking onset and elicited more advanced gait patterns (particularly in stride length) in infants with DS.

Physical Activity Patterns of Youth with Down Syndrome

The purpose of this study was to examine the physical activity patterns of children with Down syndrome. A cross-sectional approach and accelerometry were used to measure the time children with Down syndrome (N = 104) spent in sedentary, light, and moderate-to-vigorous physical activity. Results indicated that adolescents from ages 14 to 15 years were the most sedentary and spent the least amount of time in light and moderate-to-vigorous physical activity. A general trend of decreasing physical activity as children increase in age was found. This trend is similar to that found among typically developing youth. Participants in this study were found to spend a majority of their day engaged in sedentary activities. Results indicate that most participants were not accumulating the recommended 60 minutes of moderate or vigorous physical activity.

Motor Skills and Calibrated Autism Severity in Young Children With Autism Spectrum Disorder

In addition to the core characteristics of autism spectrum disorder (ASD), motor skill deficits are present, persistent, and pervasive across age. Although motor skill deficits have been indicated in young children with autism, they have not been included in the primary discussion of early intervention content. One hundred fifty-nine young children with a confirmed diagnosis of ASD (n = 110), PDD-NOS (n = 26), and non-ASD (n = 23) between the ages of 14-33 months participated in this study.1 The univariate general linear model tested the relationship of fine and gross motor skills and social communicative skills (using calibrated autism severity scores). Fine motor and gross motor skills significantly predicted calibrated autism severity (p < .05). Children with weaker motor skills have greater social communicative skill deficits. Future directions and the role of motor skills in early intervention are discussed.

Physical Activity Benefits of Learning to Ride a Two-Wheel Bicycle for Children With Down Syndrome: A Randomized Trial

Background People with Down syndrome (DS) display consistent patterns of physical inactivity. If these sedentary behaviors continue over extended periods of time, there will be negative health consequences. Objective The objective of this study was to investigate the physical activity and health-related outcomes of teaching children with DS to ride a 2-wheel bicycle. Design This study was a randomized intervention in which the control group waited 1 year to receive the intervention. Setting This intervention study was conducted in a community setting. Participants The participants were children who were 8 to 15 years of age and who had been diagnosed with DS. Intervention The participants were randomly assigned to an experimental group (bicycle intervention) or a control group (no intervention). Measurements Measurements were obtained in the month before the intervention (preintervention), at 7 weeks after the intervention, and at 12 months after the preintervention measurement for all participants. Results The results indicated no group differences at the preintervention session. Fifty-six percent of the participants in the experimental group successfully learned to ride a 2-wheel bicycle during the 5-day intervention. Analysis showed that participants who learned to ride spent significantly less time in sedentary activity at 12 months after the preintervention measurement and more time in moderate to vigorous physical activity than participants in the control group. Body fat appeared to be positively influenced over time in participants who learned to ride. Limitations It is unknown how frequently the children in the experimental group rode their bicycles after the intervention. Conclusions Most children who are 8 to 15 years of age and who have been diagnosed with DS can learn to ride a 2-wheel bicycle. Learning to ride can reduce time spent in sedentary activity and increase time spent in moderate to vigorous physical activity, which may influence the health and functioning of these children.

ALTERNATING STEPPING PATTERNS: HIDDEN ABILITIES OF 11-MONTH-OLD INFANTS WITH DOWN SYNDROME

Normally developing infants can produce organized alternating stepping patterns long before they stand alone or attempt to walk, if supported upright on a motorized treadmill. The purpose of this study was to examine whether infants with Down syndrome, who begin to walk at a much later age than non‐disabled infants, could produced alternating steps in a similar way. Six of the seven 11‐month‐old infants studied responded to the treadmill stimulus by producing alternating steps. This suggests that the basic neural substrate necessary for upright locomotion is available long before walking occurs in infants with Down syndrome, as it is in normally developing infants. The infants in this study began to walk at an average of 13·3 months after demonstrating the ability to produce treadmill steps.

Effect of Treadmill Training and Supramalleolar Orthosis Use on Motor Skill Development in Infants With Down Syndrome: A Randomized Clinical Trial

Background Children with Down syndrome (DS) often display delayed onset of independent walking. Treadmill training is an effective intervention that leads to an earlier walking onset. In addition, orthoses often are provided to infants with DS to increase stability and promote earlier independent walking. However, this early use of orthoses has not been scientifically verified in infants with DS. Objective The purpose of this study was to provide insight into the developmental outcomes of early orthosis use in combination with treadmill training in infants with DS compared with treadmill training alone. Design This study was a randomized controlled trial. Setting This study was conducted in participants’ homes and in the motor development laboratory. Participants and Intervention Seventeen infants with DS entered the study when they could pull themselves to a standing position. They were randomly assigned to either a control group (which received treadmill training) or an experimental group (which received treadmill training and orthoses). During monthly visits to the infants’ homes, 3 minutes of treadmill stepping was recorded and each childs motor development skills were tested. The treadmill training ended once the child took 3 independent steps. One month following walking onset, developmental tests were readministered. Measurements The Gross Motor Function Measure (GMFM) was used to test motor skill development. Results The average (SD) time in the study was 268 (88) days for the control group and 206 (109) days for the experimental group. All infants showed significantly increased GMFM scores over time. At 1 month of walking experience, the control group had higher GMFM scores than the experimental group, with higher standing and walking, running, and jumping subscale scores. Limitations Limitations of this study included a small sample of convenience, a statistical model that may have reduced validity at the tail end, and a lack of blinding in the GMFM scorer. Conclusions Orthoses may have a detrimental effect on overall gross motor skill development.

Effects of Various Treadmill Interventions on the Development of Joint Kinematics in Infants With Down Syndrome

Background Infants with Down syndrome (DS) have delayed walking and produce less-coordinated walking patterns. Objective The aim of this study was to investigate whether 2 treadmill interventions would have different influences on the development of joint kinematic patterns in infants with DS. Design Thirty infants with DS were randomly assigned to a lower-intensity, generalized (LG) treadmill training group (LG group) or a higher-intensity, individualized (HI) treadmill training group (HI group) and trained until walking onset. Twenty-six participants (13 in each group) completed a 1-year gait follow-up assessment. Methods During the gait follow-up assessment, reflective markers were placed bilaterally on the participants to measure the kinematic patterns of the hip, knee, and ankle joints. Both the timing and the magnitude of peak extension and flexion at the hip, knee, and ankle joints, as well as peak adduction and abduction at the hip joint, in the 2 groups were compared. Results Both the LG group and the HI group showed significantly advanced development of joint kinematics at the gait follow-up. In the HI group, peak ankle plantar flexion occurred at or before toe-off, and the duration of the forward thigh swing after toe-off increased. Limitations Joint kinematics in the lower extremities were evaluated in this study. It would be interesting to investigate the effect of treadmill interventions on kinematic patterns in the trunk and arm movement. Conclusions The timing of peak ankle plantar flexion (before toe-off) in the HI group implies further benefits from the HI intervention; that is, the HI group may use mechanical energy transfer better at the end of stance and may show decreased hip muscle forces and moments during walking. It was concluded that the HI intervention can accelerate the development of joint kinematic patterns in infants with DS within 1 year after walking onset.