Michael T Gross

University of North Carolina at Chapel Hill, North Carolina, United States

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Publications (36)87.42 Total impact

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    ABSTRACT: The injury incidence rate among runners is approximately 50%. Some individuals have advocated using an anterior-foot-strike pattern to reduce ground reaction forces and injury rates that they attribute to a rear-foot-strike pattern. The proportion of minimalist shoe wearers who adopt an anterior-foot-strike pattern remains unclear. To evaluate the accuracy of self-reported foot-strike patterns, compare negative ankle- and knee-joint angular work among runners using different foot-strike patterns and wearing traditional or minimalist shoes, and describe average vertical-loading rates. Descriptive laboratory study. Research laboratory. A total of 60 healthy volunteers (37 men, 23 women; age = 34.9 ± 8.9 years, height = 1.74 ± 0.08 m, mass = 70.9 ± 13.4 kg) with more than 6 months of experience wearing traditional or minimalist shoes were instructed to classify their foot-strike patterns. Participants ran in their preferred shoes on an instrumented treadmill with 3-dimensional motion capture. Self-reported foot-strike patterns were compared with 2-dimensional video assessments. Runners were classified into 3 groups based on video assessment: traditional-shoe rear-foot strikers (TSR; n = 22), minimalist-shoe anterior-foot strikers (MSA; n = 21), and minimalist-shoe rear-foot strikers (MSR; n = 17). Ankle and knee negative angular work and average vertical-loading rates during stance phase were compared among groups. Only 41 (68.3%) runners reported foot-strike patterns that agreed with the video assessment (κ = 0.42, P < .001). The TSR runners demonstrated greater ankle-dorsiflexion and knee-extension negative work than MSA and MSR runners (P < .05). The MSA (P < .001) and MSR (P = .01) runners demonstrated greater ankle plantar-flexion negative work than TSR runners. The MSR runners demonstrated a greater average vertical-loading rate than MSA and TSR runners (P < .001). Runners often cannot report their foot-strike patterns accurately and may not automatically adopt an anterior-foot-strike pattern after transitioning to minimalist running shoes.
    Journal of athletic training 02/2015; 50(6). DOI:10.4085/1062-6050-49.6.06 · 2.02 Impact Factor
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    Boyi Dai · William E Garrett · Michael T Gross · Darin A Padua · Robin M Queen · Bing Yu ·
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    ABSTRACT: Anterior cruciate ligament injuries (ACL) commonly occur during jump landing and cutting tasks. Attempts to land softly and land with greater knee flexion are associated with decreased ACL loading. However, their effects on performance are unclear.
    The American Journal of Sports Medicine 02/2015; 43(2):466-474. DOI:10.1177/0363546514555322 · 4.36 Impact Factor
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    ABSTRACT: A previous ergonomic screening of rice field preparation revealed farmer exposure to high risks of musculoskeletal disorders at the shoulders, hands, wrists and back. The screening method was not applied to muddy soil farming in which analysts could not observe farmer legs and feet. This study analyzed farmer pain in all stages of field preparation. To examine the relationship of farmer experience and demographics to perceptions of pain and to identify body areas exposed to ergonomics risks, unknown to farmers. Results were expected to support interventions and guidelines for famers on physical behaviors towards minimizing risk of injury as well as validation of the screening approach. Comparison of analyst screening results and farmer pain ratings using self-ratings and interviews. Farmer experience and age were significantly correlated with occurrence of pain and cramping. Less experienced farmers reported less pain in high-risk body parts (e.g., neck and lower back). More experienced farmers reported more pain in the legs, as compared with analyst risk ratings. Results demonstrated less experienced farmers to be unaware of critical areas of exposure to ergonomics risks. Correlation of farmer ratings of pain with analyst risk assessments support validity of the screening method for hazard identification and control.
    Work 11/2013; 49(1). DOI:10.3233/WOR-131768 · 0.52 Impact Factor
  • Donald Lee Goss · Michael T Gross ·
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    ABSTRACT: Study Design Observational. Objectives To compare lower extremity negative joint work and vertical ground reaction force loading rates in rearfoot-striking (RS) and Chi runners. Background Alternative running styles such as Chi running have become a popular alternative to RS running. Proponents assert that this running style reduces knee joint loading and ground reaction force loading rates. Methods Twenty-two RS and 12 Chi runners ran for 5 minutes at a self-selected speed on an instrumented treadmill. A 3-D motion analysis system was used to obtain kinematic data. Average vertical ground reaction force loading rate and negative work of the ankle dorsiflexors, ankle plantar flexors, and knee extensors were computed during the stance phase. Groups were compared using a 1-way analysis of covariance for each variable, with running speed and age as covariates. Results On average, RS runners demonstrated greater knee extensor negative work (RS, -0.332 J/body height × body weight [BH·BW]; Chi, -0.144 J/BH·BW; P<.001), whereas Chi runners demonstrated more ankle plantar flexor negative work (Chi, -0.467 J/BH·BW; RS, -0.315 J/BH·BW; P<.001). RS runners demonstrated greater average vertical ground reaction force loading rates than Chi runners (RS, 68.6 BW/s; Chi, 43.1 BW/s; P<.001). Conclusion Chi running may reduce vertical loading rates and knee extensor work, but may increase work of the ankle plantar flexors. J Orthop Sports Phys Ther 2013;43(10):685-692. Epub 9 September 2013. doi:10.2519/jospt.2013.4542.
    10/2013; 43(10):685-692. DOI:10.2519/jospt.2013.4542
  • Donald L Goss · Michael T Gross ·
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    ABSTRACT: Some runners are experimenting with barefoot or minimalist shoe running to reduce lower extremity overuse injuries. However, there has been little research to examine injury trends associated with barefoot or minimalist shoe running. To assess the association of self-reported shoe selection with reported foot strike patterns, compare overall injury incidence associated with different shoe conditions, and identify differences in injury location between different shoe conditions. Retrospective descriptive epidemiology survey. We recruited 2,509 runners (1,254 male, 1,255 female) aged 18 to 50 to complete an anonymous online survey. The survey assessed running tendencies, footstrike patterns, shoe preferences, and injury history. Reported footstrike patterns were compared among 3 shoe groups: traditionally shod, minimalist shoes, and barefoot runners. Overall and specific anatomical injury incidence was compared between traditionally shod and minimalist shoe-wearing runners. We did not include 1,605 runners in the analyses due to incomplete data or recent changes in footstrike patterns and/or shoe selection. Shoe selection was significantly associated with reported footstrike (χ² (4df) =143.4, P<.001). Barefoot and minimalist runners reported a more anterior footstrike than traditionally shod runners. Traditionally shod runners were 3.41 times more likely to report injuries than experienced minimalist shoe wearers (46.7% shod vs 13.7% minimalist, χ² (1df) =77.4, P<.001, n=888). Minimalist shoe wearers also reported fewer injuries at the hip, knee, lower leg, ankle, and foot than traditionally shod runners. Barefoot and minimalist shoe wearers reported a more anterior footstrike than traditionally shod runners. Traditionally shod runners were more likely to report injuries of the lower extremities than runners who wear minimalist shoes. Additional longitudinal prospective research is required to examine injury incidence among various footstrike patterns and shoe preferences.
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    Donald L Goss · Michael T Gross ·
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    ABSTRACT: Running related overuse injuries are a significant problem with half of all runners sustaining an injury annually. Many medical providers and coaches question how to advise their running clients to prevent injuries. Alternative running styles with a more anterior footstrike such as barefoot running, POSE running, and Chi running are becoming more popular. Little information, however, has been published comparing the mechanics and injury trends of different running styles. The original purpose of this paper was to examine evidence concerning the biomechanics and injury trends of different running styles. Little to no injury data separated by running style existed. Therefore, we discuss the biomechanics of different running styles and present biomechanical findings associated with different running injuries. English language articles published in peer reviewed journals were identified by searching PubMed, CINAHL, and SPORTDiscus databases. Nearly all of the studies identified by the search were observational studies. A more anterior initial foot contact present in barefoot or other alternative running styles may decrease or eliminate the initial vertical ground reaction peak or "impact transient," possibly reducing knee joint loads and injuries. A more anterior foot strike, however, may increase mechanical work at the ankle and tensile stress within the plantarflexors. Wearing minimal footwear may also increase contact pressure imposed on the metatarsals. More research is needed to determine which individuals with certain morphological or mechanical gait characteristics may benefit from alternative running styles that incorporate a more anterior initial foot contact with or without shoes.
  • Michael T Gross · Vicki S Mercer · Feng-Chang Lin ·
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    ABSTRACT: Controlled laboratory study using a single-cohort design. To determine if balance in older adults could be significantly improved with foot-orthotic intervention. Poor balance has been associated with risk for falls. Limited evidence exists indicating that foot orthoses influence balance. Thirteen individuals older than 65 years, who reported at least 1 unexplained fall during the past year and demonstrated poor balance, participated in the study. Subjects were tested for 1-leg stance, tandem stance, tandem gait, and alternating step tests during the first (SCREEN) and second (PRE) sessions prior to foot-orthotic intervention. Tests were repeated during the second testing session immediately after custom foot-orthotic intervention (POST) and 2 weeks following foot-orthotic use (FU). SCREEN and PRE measures were compared for stability using absolute difference computations and the Friedman rank test. PRE, POST, and FU data were analyzed using the Friedman rank test (α = .05), with Bonferroni correction for multiple post hoc comparisons. Each balance measure was statistically equivalent between the SCREEN and PRE measurements. One-leg stance times for PRE were significantly less than POST (P = .002) and FU (P = .013) measurements. Tandem stance times for PRE were significantly less than POST (P = .013) and FU (P = .013) measurements. Steps taken for the tandem gait test during the PRE measurements were significantly fewer than steps taken for the FU test (P = .007). Steps taken during the alternating step test for the PRE test were significantly fewer than steps taken during the POST (P = .002) and FU (P =.001) tests. POST and FU measurements were not significantly different for any of the 4 outcome measures. The results provide preliminary evidence that foot orthoses can effect improvement in balance measures for older adults.
    01/2012; 42(7):649-57. DOI:10.2519/jospt.2012.3944
  • Donald L. Goss · Michael T. Gross ·

    Medicine &amp Science in Sports &amp Exercise 05/2011; 43(Suppl 1):691. DOI:10.1249/01.MSS.0000401915.98164.fb · 3.98 Impact Factor
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    ABSTRACT: Patients have high reinjury rates after ACL reconstruction. Small knee flexion angles and large peak posterior ground reaction forces in landing tasks increase ACL loading. We determined the effects of a knee extension constraint brace on knee flexion angle, peak posterior ground reaction force, and movement speed in functional activities of patients after ACL reconstruction. Six male and six female patients 3.5 to 6.5 months after ACL reconstruction participated in the study. Three-dimensional videographic and force plate data were collected while patients performed level walking, jogging, and stair descent wearing a knee extension constraint brace, wearing a nonconstraint brace, and not wearing a knee brace. Knee flexion angle at initial foot contact with the ground, peak posterior ground reaction force, and movement speed were compared across brace conditions and between genders. Wearing the knee extension constraint brace increased the knee flexion angle at initial foot contact for each activity when compared with the other two brace conditions. Wearing the knee extension constraint brace also decreased peak posterior ground reaction force during walking but not during jogging and stair descent. Although the knee extension constraint brace did not consistently reduce the peak posterior ground reaction force in all functional activities, it consistently increased knee flexion angle and should reduce ACL loading as suggested by previous studies. These results suggest the knee extension constraint brace has potential as a rehabilitation tool to alter lower extremity movement patterns of patients after ACL reconstruction to address high reinjury rates.
    Clinical Orthopaedics and Related Research 10/2010; 469(6):1774-80. DOI:10.1007/s11999-010-1633-9 · 2.77 Impact Factor
  • Vicki Stemmons Mercer · Michael T Gross · Subhashini Sharma · Erin Weeks ·
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    ABSTRACT: Step-up exercises often are suggested for strengthening the hip abductor muscles and improving balance in older adults. Little is known, however, about whether the forward or lateral version of these exercises is best for activating the hip abductor muscles. The purpose of this study was to examine the electromyographic (EMG) amplitude of the gluteus medius (GM) muscles bilaterally during forward and lateral step-up exercises. The study design involved single-occasion repeated measures. Twenty-seven community-dwelling adults (7 men and 20 women) with a mean (SD) age of 79.4 (8.0) years performed forward and lateral step-up exercises while the surface EMG activity of the GM muscles was recorded bilaterally. Pressure switches and dual forceplates were used to identify the ascent and descent phases. Subjects were instructed to lead with the right lower extremity during ascent and the left lower extremity during descent. Differences in normalized root-mean-square EMG amplitudes with exercise direction (forward versus lateral) and phase (ascent versus descent) were examined by use of separate repeated-measures analyses of variance for the right and left lower extremities. The alpha level was set at .05. Gluteus medius muscle EMG activity was significantly greater for lateral than for forward step-up exercises for the left lower extremity during the ascent phase and for both lower extremities during the descent phase. In addition, right GM muscle EMG activity was significantly greater during ascent than during descent for both exercise directions. Study limitations include use of a convenience sample and collection of limited information about participants. Step-up exercises are effective in activating the GM muscle, with lateral step-up exercises requiring greater GM muscle activation than forward step-up exercises. Further study is needed to determine whether exercise programs for hip abductor muscle strengthening in older adults should preferentially include lateral over forward step-up exercises.
    Physical Therapy 09/2009; 89(11):1205-14. DOI:10.2522/ptj.20080229 · 2.53 Impact Factor
  • Michael T. Gross · Carol Giddings Cochrane ·
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    ABSTRACT: The authors describe a method that can be used to quantify the reset of activity cycles to spontaneous infants kicking. This method employs a video system to record and view infant kicking behavior, and a digitizing system to track the position of the lateral malleolus through space. Rest and activity cycles are operationally defined in terms of displacement of the lateral malleolus relative to infant leg length. The authors provide the computer software necessary to implement this method, and suggest tat this specific method or a method derived from this general strategy may be useful in this study of human activity and rest periods.
    Physical & Occupational Therapy in Pediatrics 07/2009; 8(2-3):59-70. DOI:10.1080/J006v08n02_04 · 1.46 Impact Factor
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    Scott E Ross · Kevin M Guskiewicz · Michael T Gross · Bing Yu ·
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    ABSTRACT: To identify force plate measures that discriminate between ankles with functional instability and stable ankles and to determine the most accurate force plate measure for enabling this distinction. Twenty-two subjects (177 +/- 10 cm, 77 +/- 16 kg, 21 +/- 2 yr) without a history of ankle injury and 22 subjects (177 +/- 10 cm, 77 +/- 16 kg, 20 +/- 2 yr) with functional ankle instability (FAI) performed a single-leg static balance test and a single-leg jump-landing dynamic balance test. Static force plate measures analyzed in both anterior/posterior (A/P) and medial/lateral (M/L) directions included the following: ground reaction force (GRF) SD; center-of-pressure (COP) SD; mean, maximum, and total COP excursion; and mean and maximum COP velocity. COP area was also analyzed for static balance. A/P and M/L time to stabilization quantified dynamic balance. Greater values of force plate measures indicated impaired balance. A stepwise discriminant function analysis examined group differences, group classification, and accuracy of force plate measures for discriminating between ankle groups. The FAI group had greater values than the stable ankle group for A/P GRF SD (P = 0.027), M/L GRF SD (P = 0.006), M/L COP SD (P = 0.046), A/P mean COP velocity (P = 0.015), M/L mean COP velocity (P = 0.016), A/P maximum COP velocity (P = 0.037), M/L mean COP excursion (P = 0.014), M/L total COP excursion (P = 0.016), A/P time to stabilization (P = 0.011), and M/L time to stabilization (P = 0.040). M/L GRF SD and A/P time to stabilization had the greatest accuracy scores of 0.73 and 0.72, respectively. Although 10 measures identified group differences, M/L GRF SD and A/P time to stabilization were the most accurate in discriminating between ankle groups. These results provide evidence for choosing these GRF measures for evaluating static and dynamic balance deficits associated with FAI.
    Medicine and science in sports and exercise 02/2009; 41(2):399-407. DOI:10.1249/MSS.0b013e3181872d89 · 3.98 Impact Factor
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    Steve Leigh · Michael T Gross · Li Li · Bing Yu ·
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    ABSTRACT: The aim of this study was to determine the relationship between discus throwing performance and the following technical parameters: hip-shoulder and shoulder-arm separation, trunk forward-backward tilt, throwing-arm elevation angles, and the absolute and relative throwing procedure phase times. Videographic data of 51 male and 53 female discus throwers' competitive performances were captured during major meets. The three-dimensional coordinates of 21 body landmarks and the discus were obtained for each thrower's best trial using direct linear transformation. The technical parameters were reduced from the three-dimensional data at six critical instants during the throwing procedure. Hierarchical stepwise multiple regression analyses were performed to determine the relative influence of linear combinations of the technical parameters on discus throwing performance. Specific techniques associated with linear combinations of certain technical parameters were identified using canonical correlations. Males and females were analysed separately. Suggestions for controlling the height of release and the vertical component of the speed of release using an effective technique are made.
    Sports Biomechanics 06/2008; 7(2):173-93. DOI:10.1080/14763140701841399 · 1.15 Impact Factor
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    Scott E Ross · Kevin M Guskiewicz · Michael T Gross · Bing Yu ·
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    ABSTRACT: Assessment tools should identify functional limitations associated with functional ankle instability (FAI) by discriminating unstable from stable ankles. To identify assessment tools that discriminated FAI from stable ankles and determine the most accurate assessment tool for discriminating between FAI and stable ankles. Case-control study. Research laboratory. Fifteen individuals with FAI and 15 healthy individuals; participants with unilateral FAI reported "giving-way" sensations and ankle sprains, whereas healthy participants did not. Participants answered 12 questions on the Ankle Joint Functional Assessment Tool (AJFAT). They also performed a single-leg jump landing, which required them to jump to half their maximum jump height, land on a single leg, and stabilize quickly on a force plate. Receiver operating characteristic curves determined cutoff scores for discriminating between ankle groups for AJFAT total score and resultant vector (RV) time to stabilization. Accuracy values for discriminating between groups were determined by calculating the area under the receiver operating characteristic curves. The cutoff score for discriminating between FAI and stable ankles was > or =26 (sensitivity = 1, specificity = 1) and > or =1.58 seconds (sensitivity = 0.67, specificity = 0.73) for the AJFAT total score and RV time to stabilization, respectively. The area under the curve for the AJFAT was 1.0 (asymptotic significance <.05), whereas the RV time to stabilization had an area under the curve of 0.72 (asymptotic significance <.05). The AJFAT was an excellent assessment tool for discriminating between ankle groups, whereas RV time to stabilization was a fair assessment tool. Although both assessments discriminated between ankle groups, the AJFAT more accurately discriminated between groups than the RV time to stabilization did. Future researchers should confirm these findings using a prospective research design.
    Journal of athletic training 01/2008; 43(1):44-50. DOI:10.4085/1062-6050-43.1.44 · 2.02 Impact Factor
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    ABSTRACT: Preintervention and post-intervention, repeated-measures experimental design. The objective was to investigate the effects of foot orthoses with medial arch support on ankle inversion angle and plantar forces and pressures on the fifth metatarsal during landing for a basketball lay-up and during the stance phase of a shuttle run. Proximal fractures of the fifth metatarsal, specifically the Jones fracture, are common in sports. Wearing foot orthoses with medial arch support could increase the ankle inversion angle and the plantar forces and pressure on the fifth metatarsal that may increase the risk for fifth metatarsal fracture, Three-dimensional (3-D) videographic, force plate, and in-shoe plantar force and pressure data were collected during landing after a basketball lay-up and during the stance phase of a shuttle run with and without foot orthoses with medial arch support for 14 male subjects. Two-way ANOVAs with repeated measures were performed to compare ankle inversion angle, maximum forces, and pressure on the fifth metatarsal head and base between conditions and between tasks. The maximum ankle inversion angle and maximum plantar force and pressure on the base of the fifth metatarsal during both tasks as well as the maximum plantar force and pressure on the head of the fifth metatarsal during the stance of the shuttle run were significantly increased (P< or =026) when wearing foot orthoses. No significant differences were found in the maximum vertical ground reaction forces between foot orthotic conditions. Generic use of off-the-shelf foot orthoses with medial arch support causes increased plantar forces and pressures on the fifth metatarsal and may increase the risk for proximal fracture of the fifth metatarsal. Future studies are needed to investigate this risk, acknowledging that the differences noted in our study were small in magnitude and the foot type was not measured.
    Journal of Orthopaedic and Sports Physical Therapy 05/2007; 37(4):186-91. DOI:10.2519/jospt.2007.2327 · 3.01 Impact Factor
  • Liang-Ching Tsai · Bing Yu · Vicki S Mercer · Michael T Gross ·
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    ABSTRACT: Matched group comparison of 3 subject groups with 3 different foot structures for force plate and clinical measures of postural control. To determine if subjects with different weight-bearing foot structure would demonstrate differences in static standing postural control, and to determine the reliability of study procedures. Weight-bearing foot structure may influence postural control either because of a decreased base of support (supinated foot structure) or because of passive instability of the joints of the foot (pronated foot structure). Young adults were categorized based on weight-bearing foot structure into neutral, pronated, or supinated groups (15 subjects per group). Postural control in single-limb stance with eyes closed was assessed using force plate measures and by measuring duration of single-limb stance on a firm floor and on a balance pad. Force plate measures were normalized center-of-pressure average speed; and standard deviation and maximum displacement in the anterior-posterior and medial-lateral directions. Individuals in the supinated group had significantly greater center-of-pressure average speed, greater maximum displacement in the anterior-posterior direction, and greater SD and maximum displacement in the medial-lateral direction than individuals in the neutral group. The individuals in the pronated group had significantly greater SD and maximum displacement in the anterior-posterior direction, used more trials to complete force plate testing, and had shorter single-limb stance duration than those in the neutral group. Individuals with pronated feet or supinated feet have poorer postural control than individuals with neutral feet, but perhaps through different mechanisms.
    Journal of Orthopaedic and Sports Physical Therapy 01/2007; 36(12):942-53. DOI:10.2519/jospt.2006.2336 · 3.01 Impact Factor
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    Robin M Queen · Michael T Gross · Hsin-Yi Liu ·
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    ABSTRACT: The purpose of this study was to determine the effects of self-selected versus standardized running speeds on within-day and between-day repeatability of lower extremity kinematics and kinetics for running gait. Subjects (six female, six male, age 18-35) were recreational athletes with no lower extremity injuries. The following study variables were analyzed using the coefficient of variation (CV): the peak angles for knee internal rotation, external rotation, varus, valgus, flexion, and extension; peak angles for ankle dorsiflexion and plantar flexion; peak impact force and propulsive force; and peak anterior, posterior, medial, and lateral ground reaction forces (GRFs). Data for the entire stance phase were analyzed using the coefficient of multiple correlation (CMC) for the following variables: anterior-posterior, medial-lateral, and vertical GRF; the angles and angular velocities for knee internal-external rotation, valgus-varus, flexion-extension, and ankle dorsiflexion-plantar flexion. Each variable was analyzed using a 2 x 2 (speed x day) repeated measures ANOVA (alpha = 0.05). The within-day repeatability for all of the significantly different variables was greater than the between-day repeatability. For variables with a significant difference based on speed, the standardized running speed had greater repeatability. Within-day repeatability is generally greater than between-day repeatability. Running speed had little effect on the repeatability of any study variable. Having subjects run at a standardized speed may not be as important as previously thought.
    Gait & Posture 05/2006; 23(3):282-7. DOI:10.1016/j.gaitpost.2005.03.007 · 2.75 Impact Factor
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    Charles A Thigpen · Michael T Gross · Spero G Karas · William E Garrett · Bing Yu ·
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    ABSTRACT: Measurement of scapular kinematics is an important component in the assessment of shoulder function; however, repeatability of these measurements has not been established. The purpose of this study, therefore, was to determine the repeatability of scapular rotation measures for different humeral elevation planes between trials, sessions, and days. Three-dimensional scapular rotations were collected using an electromagnetic tracking system in three planes of humeral elevation. Coefficient of multiple correlation (CMC) values were calculated between trials, sessions, and days for curves of scapular rotations. CMC values were compared with repeated measures analysis of variance (ANOVAs) and Tukey's post-hoc procedures. Tests of simple main effects were performed for significant interaction effects. Our results suggest that scapular rotation measures are repeatable between trials within the same testing session, but less repeatable between testing sessions and days. Sagittal plane elevation consistently yielded the highest CMC values for all scapular rotations. These results suggest sagittal plane elevation should be considered to evaluate differences in scapular rotations.
    Research in Sports Medicine 07/2005; 13(3):181-98. DOI:10.1080/15438620500222489 · 1.70 Impact Factor
  • Robin M. Queen · Michael T. Gross · Hsin-Yi Liu ·

    Medicine &amp Science in Sports &amp Exercise 05/2005; 37(Supplement). DOI:10.1097/00005768-200505001-01820 · 3.98 Impact Factor
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    Lisa B Johnston · Michael T Gross ·
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    ABSTRACT: Repeated-measures analysis of intervention. To determine the effects of foot orthoses on quality of life for individuals with patellofemoral pain who demonstrate excessive foot pronation. Foot orthoses are a common intervention for patients with patellofemoral pain. Limited information is available, however, regarding the effects of foot orthoses on quality of life for these patients. Sixteen subjects with patellofemoral pain who also exhibited signs of excessive foot pronation were studied. Subjects underwent a 2-week period of baseline study followed by custom foot orthotic intervention. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was administered to subjects at the time of screening, just prior to foot orthotic intervention, and at 2 weeks and 3 months following foot orthotic intervention. Wilcoxon matched-pairs signed-rank test results indicated statistically significant improvements in the pain and stiffness subscales 2 weeks following the start of foot orthotic intervention. All WOMAC subscale scores were significantly improved at 3 months compared with preintervention measurements. Custom-fitted foot orthoses may improve patellofemoral pain symptoms for patients who demonstrate excessive foot pronation.
    Journal of Orthopaedic and Sports Physical Therapy 09/2004; 34(8):440-8. DOI:10.2519/jospt.2004.1384 · 3.01 Impact Factor

Publication Stats

858 Citations
87.42 Total Impact Points


  • 1994-2015
    • University of North Carolina at Chapel Hill
      • Sports Medicine Research Laboratory
      North Carolina, United States
  • 2008
    • Virginia Commonwealth University
      • Department of Health and Human Performance
      Richmond, Virginia, United States