damaged sensory receptors and changed muscular adjustment patterns, trigger instability in postural balance and limited trunk movement adjustment. 6 The traditional stabilizing exercise interventions are successful at treating LBP; however, there is often recurrence of LBP that has been illustrated in
Yong Wook Kim, Na Young Kim, Won Hyuk Chang and Sang Chul Lee
Chi-Whan Choi, Jung-Wan Koo and Yeon-Gyu Jeong
° bench while side lying (TLBS), elevating the torso while standing on a 45° bench with the feet anchored; or wall side bridge (WSB), side-bridge exercises while standing against a wall despite a compromised shoulder, hip, or knee. 4 , 9 , 10 However, the comparative effects of these traditional side
Katherine Histen, Julia Arntsen, Lauren L’Hereux, James Heeren, Benjamin Wicki, Sterling Saint, Giselle Aerni, Craig R. Denegar and Michael F. Joseph
Tendon adapts to load through alterations in its composition and mechanical properties. Mechanical adaptation to increased load often involves increases in cross-sectional area (CSA), stiffness, and modulus. Runners exhibit these adaptations.
To determine if runners wearing minimalist shoes had larger and stiffer Achilles tendons (AT) than traditionally shod runners.
Cross-sectional study of well-trained, traditionally and minimally shod runners.
Laboratory assessment of trained runners.
23 men (11 traditional, 12 minimalist) and 8 women (6 traditional, 2 minimalist). Runners wearing minimalist shoes had 4.2 ± 1.6 y of training experience in minimalist shoes.
Main Outcome Measures:
The authors used diagnostic ultrasound and isokinetic dynamometry to generate a force-elongation curve and its derivatives.
Minimalist runners had a greater CSA: mean difference (MD) = 9.2 mm2, stiffness (MD = 268.1 N/mm), and modulus (MD = 202.9 MPa). ATs of minimalist runners experienced greater stress (MD 8.6 N/mm2) during maximal voluntary isometric contraction of the plantar-flexor muscles due to greater force of contraction (MD 798.9 N).
The AT in minimalist runners adapts by increasing size, stiffness, and modulus, which is consistent with our understanding of mechanical adaptation of tendon to increased loading. Increased stress to the AT likely requires a slow transition to minimalist running to allow the AT to adapt without evidence of injury.
Matthew K. Seeley, Iain Hunter, Thomas Bateman, Adam Roggia, Brad J. Larson and David O. Draper
A novel spring-loaded-crutch design may provide patients additional forward velocity, relative to traditional axillary crutches; however, this idea has not yet been evaluated.
To quantify elastic potential energy stored by spring-loaded crutches during crutch–ground contact and determine whether this energy increases forward velocity for patients during crutch ambulation. Because elastic potential energy is likely stored by the spring-loaded crutch during ambulation, the authors hypothesized that subjects would exhibit greater peak instantaneous forward velocity during crutch–ground contact and increased preferred ambulation speed during spring-loaded-crutch ambulation, relative to traditional-crutch ambulation.
10 healthy men and 10 healthy women.
The independent variable was crutch type: Subjects used spring-loaded and traditional axillary crutches to ambulate at standardized and preferred speeds.
Main Outcome Measures:
The primary dependent variables were peak instantaneous forward velocity and preferred ambulation speed; these variables were quantified using high-speed videography and an optoelectronic timing device, respectively. Between-crutches differences for the dependent variables were evaluated using paired t tests (α = .05). Elastic potential energy stored by the spring-loaded crutches during crutch–ground contact was also quantified via videography.
Peak forward velocity during crutch–ground contact was 5% greater (P < .001) for spring-loaded-crutch ambulation than for traditional-crutch ambulation. Preferred ambulation speed, however, did not significantly differ (P = .538) between crutch types. The spring-loaded crutches stored an average of 2.50 ± 1.96 J of elastic potential energy during crutch–ground contact.
The spring-loaded crutches appear to have provided subjects with additional peak instantaneous forward velocity. This increased velocity, however, was relatively small and did not increase preferred ambulation speed.
Robert S. Thiebaud, Takashi Abe, Jeremy P. Loenneke, Tyler Garcia, Yohan Shirazi and Ross McArthur
flow and shows that more care should be taken when suggesting how much stretch should be used when applying elastic knee wraps. We also found that when practical and traditional BFR exercises are done to failure, small differences in changes from preexercise to postexercise in MT and MVC are found. We
Amador García-Ramos, Slobodan Jaric, Paulino Padial and Belén Feriche
This study aimed to (1) evaluate the linearity of the force–velocity relationship, as well as the reliability of maximum force (F 0), maximum velocity (V 0), slope (a), and maximum power (P 0); (2) compare these parameters between the traditional and ballistic bench press (BP); and (3) determine the correlation of F 0 with the directly measured BP 1-repetition maximum (1RM). Thirty-two men randomly performed 2 sessions of traditional BP and 2 sessions of ballistic BP during 2 consecutive weeks. Both the maximum and mean values of force and velocity were recorded when loaded by 20–70% of 1RM. All force–velocity relationships were strongly linear (r > .99). While F 0 and P 0 were highly reliable (ICC: 0.91–0.96, CV: 3.8–5.1%), lower reliability was observed for V 0 and a (ICC: 0.49–0.81, CV: 6.6–11.8%). Trivial differences between exercises were found for F 0 (ES: < 0.2), however the a was higher for the traditional BP (ES: 0.68–0.94), and V 0 (ES: 1.04–1.48) and P 0 (ES: 0.65–0.72) for the ballistic BP. The F 0 strongly correlated with BP 1RM (r: 0.915–0.938). The force–velocity relationship is useful to assess the upper body maximal capabilities to generate force, velocity, and power.
Joanna E. Gelinas and Greg Reid
The purpose was to determine whether traditional learn-to-swim progressions, leading to a 10-m front and 10-m back swim, were developmentally valid for children with physical disabilities. Forty children (22 boys, 18 girls) ages 5 to 12 years participated. They were classified according to disability type, functional sport classification, mode of ambulation, and flotation device use. Developmental validity was assessed by testing the children on rhythmic breathing, front float, front glide, front swim, back float, back glide, and back swim. Each skill was deemed successful if the child accomplished all performance criteria of that skill. Atypical progression was evident if a child performed a skill without the ability to perform skills previously listed in that progression. Atypical progression occurred in 32 (80%) children in the front skills and 22 (55%) in the back skills, which indicates that the traditional learn-to-swim progressions for both the 10-m front swim and the 10-m back swim were not developmentally valid for most children with physical disabilities in the conducted research.
April J. Chambers, Alison L. Sukits, Jean L. McCrory and Rakié Cham
Age, obesity, and gender can have a significant impact on the anthropometrics of adults aged 65 and older. The aim of this study was to investigate differences in body segment parameters derived using two methods: (1) a dual-energy x-ray absorptiometry (DXA) subject-specific method (Chambers et al., 2010) and (2) traditional regression models (de Leva, 1996). The impact of aging, gender, and obesity on the potential differences between these methods was examined. Eighty-three healthy older adults were recruited for participation. Participants underwent a whole-body DXA scan (Hologic QDR 1000/W). Mass, length, center of mass, and radius of gyration were determined for each segment. In addition, traditional regressions were used to estimate these parameters (de Leva, 1996). A mixed linear regression model was performed (α = 0.05). Method type was significant in every variable of interest except forearm segment mass. The obesity and gender differences that we observed translate into differences associated with using traditional regressions to predict anthropometric variables in an aging population. Our data point to a need to consider age, obesity, and gender when utilizing anthropometric data sets and to develop regression models that accurately predict body segment parameters in the geriatric population, considering gender and obesity.
Rebecca J. Guthrie, Terry L. Grindstaff, Theodore Croy, Christopher D. Ingersoll and Susan A. Saliba
Individuals with low back pain (LBP) are thought to benefit from interventions that improve motor control of the lumbopelvic region. It is unknown if therapeutic exercise can acutely facilitate activation of lateral abdominal musculature.
To investigate the ability of 2 types of bridging-exercise progressions to facilitate lateral abdominal muscles during an abdominal drawing-in maneuver (ADIM) in individuals with LBP.
Randomized control trial.
University research laboratory.
51 adults (mean ± SD age 23.1 ± 6.0 y, height 173.6 ± 10.5 cm, mass 74.7 ± 14.5 kg, and 64.7% female) with LBP. All participants met 3 of 4 criteria for stabilization-classification LBP or at least 6 best-fit criteria for stabilization classification.
Participants were randomly assigned to either traditional-bridge progression or suspension-exercise-bridge progression, each with 4 levels of progressive difficulty. They performed 5 repetitions at each level and were progressed based on specific criteria.
Main Outcome Measures:
Muscle thickness of the external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) was measured during an ADIM using ultrasound imaging preintervention and postintervention. A contraction ratio (contracted thickness:resting thickness) of the EO, IO, and TrA was used to quantify changes in muscle thickness.
There was not a significant increase in EO (F 1,47 = 0.44, P = .51) or IO (F 1,47 = .30, P = .59) contraction ratios after the exercise progression. There was a significant (F 1,47 = 4.05, P = .05) group-by-time interaction wherein the traditional-bridge progression (pre = 1.55 ± 0.22; post = 1.65 ± 0.21) resulted in greater (P = .03) TrA contraction ratio after exercise than the suspension-exercise-bridge progression (pre = 1.61 ± 0.31; post = 1.58 ± 0.28).
A single exercise progression did not acutely improve muscle thickness of the EO and IO. The magnitude of change in TrA muscle thickness after the traditional-bridging progression was less than the minimal detectable change, thus not clinically significant.
Scott Cheatham, Morey J. Kolber and Michael P. Ernst
Pulse oximetry has become mobile with the use of smartphone and Bluetooth wireless technology. This technology offers many benefits but has not been extensively studied. There is a need to further validate its clinimetric properties for health professionals to provide proper guidance to patients.
This investigation assessed the concurrent validity of the iSpO2 pulse oximeter against a traditional pulse oximeter in measuring short-term resting blood oxygen saturation (SpO2) and pulse rate.
Observational study of reliability.
University kinesiology laboratory.
Thirty healthy, recre-ationally active adults (18 men, 12 women; mean age = 25.7 ± 5.46 years, mean height = 170.3cm ± 9.51, mean body mass = 76.4 kg ± 19.33).
Resting measurement of SpO2 and pulse rate using the iSpO2 pulse oximeter with the iPad Mini and a traditional pulse oximeter with Bluetooth.
Main Outcome Measure:
Resting SpO2 and pulse rate were concurrently measured over 5 min.
The concurrent validity between the iSpO2 and traditional pulse oximeter was moderate for measuring SpO2, intraclass correlation coeffcient (ICC)(3, 1) = .73, SEM = 0.70%, and good for pulse rate, ICC(3, 1) = .97, SEM = 1.74 beats per minute (bpm). The minimal detectable change at the 95% confidence interval for both instruments suggests that there may be 1.94% disagreement for SpO2 and 4.82 bpm disagreement between pulse oximetry methods. The 95% limits of agreement (LoA) for measuring SpO2 suggests that the iSpO2 and traditional pulse oximeters may vary -0.28 ± 1.98%, or approximately 2%. The 95% LoA for measuring pulse rate suggests that the iSpO2 and traditional pulse oximeter may vary 1.74 ± 4.98 bpm, potentially upward of 6 bpm. On the basis of the results of the LoA, it appears that there may be a slight systematic bias between the two devices, with the traditional pulse oximeter producing higher pulse rates than the iSpO2.
The findings suggest that both instruments may be beneficial for indirect short-term measurements of resting SpO2 and pulse rate.