Albuterol aids resistance exercise in reducing unloading-induced ankle extensor strength losses

2005 ◽  
Vol 98 (5) ◽  
pp. 1705-1711 ◽  
Author(s):  
John Caruso ◽  
John Hamill ◽  
Miki Yamauchi ◽  
Dean Mercado ◽  
Tim Cook ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Repeated Measures ◽  
Weight Bearing ◽  
Average Power ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Short Term ◽  
Cross Sectional ◽  
Honestly Significant Difference ◽  
Significant Difference

While resistance exercise (REX) reduces ankle extensor (AE) mass and strength deficits during short-term unloading; additional treatments, concurrently administered with REX, are required to attenuate the greater losses seen with longer unloading periods. Subjects performed left leg REX, which otherwise refrained from ambulatory and weight-bearing activity for 40 days, while randomized to a capsule (placebo, albuterol) dosing regimen with no crossover to note whether albuterol helps REX mitigate unloading-induced AE losses. A third group of subjects served as unloaded controls. On days 0, 20, and 40, the following data were collected from the left leg: calf cross-sectional area and AE strength measures. Cross-sectional area was estimated using anthropometric methodology, whereas AE strength data were obtained from eight unilateral calf-press repetitions on an inertial-based REX device. Repeated-measures mixed-factorial 3 × 3 analyses of covariance, with day 0 values as a covariate, revealed group × time interactions for the strength variables eccentric total work (ETW) and average power (EAP). Tukey's honestly significant difference shows REX-placebo subjects incurred significant ETW and EAP losses by day 40, whereas the REX-albuterol treatment evoked strength gains to those same variables without concurrent muscle accretion. Corresponding concentric variables did not display similar changes. Day 40 control data significantly declined for many variables; relative to the REX-albuterol treatment, some losses were significant after 20 days. ETW and EAP gains to unloaded AE may be due to one or more mechanisms. Continued research identifying mechanisms responsible for such changes, as well as the safety of REX-albuterol administration in other models, is warranted.

scholarly journals Effect of Different Exercise Types on the Cross-Sectional Area and Lumbar Lordosis Angle in Patients with Flat Back Syndrome

2021 ◽  
Vol 18 (20) ◽  
pp. 10923
Author(s):  
Won-Moon Kim ◽  
Yong-Gon Seo ◽  
Yun-Jin Park ◽  
Han-Su Cho ◽  
Chang-Hee Lee
Keyword(s):  
Resistance Exercise ◽  
Lumbar Lordosis ◽  
Exercise Group ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Exercise Programs ◽  
Cross Sectional ◽  
Significant Difference ◽  
The Cross ◽  
Flat Back

Flat back syndrome (FBS) is a sagittal imbalance wherein the normal spinal curvature is reduced. This study aimed to compare the effects of different exercise programs on the cross-sectional area (CSA) of the lumbar muscles, lumbar lordosis angle (LLA), lumbar disability, and flexibility in patients with FBS. Thirty-six females with flexible FBS were randomly allocated to the corrective exercise group (CEG, n = 12), resistance exercise group (REG, n = 12), and physical therapy group (PTG, n = 12). CEG and REG patients participated in a 12-week exercise intervention for 60 min three times per week. The CSA, LLA, Oswestry disability index (ODI), and sit-and-reach test were measured before and after intervention. CSA showed a significant difference between groups (p < 0.01), with CEG and REG demonstrating a significant increase (p < 0.05 and p < 0.05, respectively). LLA showed a significant difference between groups (p < 0.001); CEG showed a higher increase than did REG (p < 0.01) and PTG (p < 0.001). ODI also showed a significant difference between groups (p < 0.001), being lower in CEG than in REG (p < 0.001) and PTG (p < 0.001). Lumbar flexibility significantly improved in all groups, albeit with a significant difference (p < 0.001). Although corrective and resistance exercise programs effectively improve these parameters, corrective exercise is superior to other interventions for patients with FBS.

scholarly journals Effect of shoulder positioning on ultrasonic visualisation of the subclavian vein in healthy adults: A prospective observational study

2021 ◽  
pp. 102490792110009
Author(s):  
Hei Jim Leung ◽  
Lok Yu Wong ◽  
Chi Shing Pak ◽  
Yang Li Chuan Marc
Keyword(s):  
Observational Study ◽  
Repeated Measures ◽  
Subclavian Vein ◽  
Prospective Observational Study ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Significant Difference ◽  
The Cross ◽  
The Right

Introduction: Ultrasound guidance is commonly used during central venous cannulation. Subclavian vein is a commonly chosen site, but previous studies found varying results in the ideal positioning of the shoulder for subclavian vein cannulation. The objective of this study is to determine which shoulder position results in the greatest cross-sectional area of the right subclavian vein for cannulation. Methods: In this prospective observational study, ultrasound was performed on healthy adult volunteers to visualise the right subclavian vein in three different shoulder positions: neutral, abduction and retraction. A blinded independent investigator measured the cross-sectional areas by computer software using planimetry method. Statistical analysis was performed by one-way repeated measures analysis of variance. Results: Forty-four adults participated in the study. The mean cross-sectional area of the right subclavian vein in shoulder neutral, abduction and retraction positions were 1.05 ± 0.33 cm2, 1.01 ± 0.31 cm2 and 0.82 ± 0.28 cm2, respectively. When compared to shoulder retraction, the cross-sectional areas were significantly increased in shoulder neutral ( P < 0.01) and abduction ( P < 0.01) positions. There was no significant difference between shoulder neutral and abduction position ( P = 0.71). Conclusion: Positioning the shoulder in neutral or abduction results in the greatest cross-sectional area of the right subclavian vein and may be more ideal for ultrasound guided cannulation.

Intra- and inter-rater reliability for the measurement of the cross-sectional area of ankle tendons assessed by magnetic resonance imaging

2021 ◽  
pp. 028418512110032
Author(s):  
Henrique Mansur ◽  
Guilherme Estanislau ◽  
Marcos de Noronha ◽  
Rita de Cassia Marqueti ◽  
Emerson Fachin-Martins ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Repeated Measures ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Resonance Imaging ◽  
Cross Sectional ◽  
Rater Reliability ◽  
The Cross ◽  
Very High

Background The cross-sectional area (CSA) records make an essential measurement for determining the mechanical properties of tendons, such as stress and strength. However, there is no consensus regarding the best method to record the CSA from different tendons. Purpose To determine intra- and inter-rater reliability for CSA measures from magnetic resonance imaging (MRI) of the following tendons: tibialis anterior; tibialis posterior; fibularis longus and brevis; and Achilles. Material and Methods We designed an observational study with repeated measures taken from a convenience sample of 20 participants diagnosed with acute or chronic ankle sprain. Two independent raters took three separate records from the CSA of ankle tendon images of each MRI slice. The intra-class correlation coefficient (ICC) and 95% limits of agreement (LoA) defined the quality (associations) and magnitude (differences), respectively, of intra- and inter-rater reliability on the measures plotted by the Bland–Altman method. Results Data showed very high intra- and inter-rater correlations for measures taken from all tendons analyzed (ICC 0.952–0.999). It also revealed an excellent agreement between raters (0.12%–2.3%), with bias no higher than 2 mm2 and LoA in the range of 4.4–7.9 mm2. The differences between repeated measures recorded from the thinnest tendons (fibularis longus and brevis) revealed the lowest bias and narrowest 95% LoA. Conclusion Reliability for the CSA of ankle tendons measured from MRI taken by independent rates was very high, with the smallest differences between raters observed when the thinnest tendon was analyzed.

Guideline Values for Minimum Nasal Cross-Sectional Area in Children

2018 ◽  
Vol 55 (8) ◽  
pp. 1043-1050
Author(s):  
Maija T. Laine-Alava ◽  
Siiri Murtolahti ◽  
Ulla K. Crouse ◽  
Donald W. Warren
Keyword(s):  
Cleft Lip ◽  
Cross Sectional Area ◽  
Adult Size ◽  
Nasal Airway ◽  
Sectional Area ◽  
Cross Sectional ◽  
Age Cohorts ◽  
Guideline Values ◽  
Significant Difference ◽  
Research Criteria

Objective: The purpose was to determine age-specific values of the minimum cross-sectional area of the nasal airway in children without cleft lip or palate and to assess whether gender differences occur with growth in order to develop guidelines for assessment in children with clefts. Participants: All schoolchildren aged 8 to 17 years who met the research criteria were studied during rest breathing using the pressure-flow technique. The children came from a rural area of 3800 inhabitants. Consecutive age cohorts were used for comparisons. Results: Nasal cross-sectional area increased in females from 0.38 cm2 in 8-year-olds to 0.58 cm2 in 17-year-olds. There was a decrease in size at ages 10 to 11 and 14 to 15 years. In males, the area increased from 0.40 to 0.68 cm2 and decreased slightly from 9 to 10 and 14 to 15 years. The annual changes were statistically significant in females between 8 and 9 and 11 to 13 years of age, and in males from 11 to 12, 13 to 14, and 15 to 17 years of age. Across gender, the only significant difference occurred at age 16. Conclusions: Our results indicate that the increase in nasal airway size is not consistent during growth. Nasal airway size showed almost equal values for both genders in young children but was systematically larger in boys from 14 years of age on. The results refer that by 17 years of age nasal airway may not have reached adult size in males.

Relevance of classification by size to topographical differences in bronchial smooth muscle response

1993 ◽  
Vol 75 (5) ◽  
pp. 2013-2021 ◽  
Author(s):  
P. Chitano ◽  
S. B. Sigurdsson ◽  
A. J. Halayko ◽  
N. L. Stephens
Keyword(s):  
Smooth Muscle ◽  
Electrical Field Stimulation ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Muscle Response ◽  
Bronchial Responsiveness ◽  
Sixth Generation ◽  
Significant Difference ◽  
And Control

To investigate heterogeneity of airway smooth muscle response, we studied strips of large and small branches from third- to sixth-generation bronchi obtained from ragweed antigen-sensitized and control dogs. The response to electrical field stimulation and carbamylcholine chloride was greater in strips from larger branches of the same generation when expressed as "tissue stress" (force per unit cross-sectional area of the whole tissue), whereas no difference emerged with use of the more appropriate "smooth muscle stress" (force per unit cross-sectional area of the muscle tissue). The response to histamine was significantly higher in small branches than in large ones, and histamine sensitivity [mean effective concentration (EC50)] was 7.79 x 10(-6) [geometric standard error of the mean (GSEM) 1.20] and 1.49 x 10(-5) M (GSEM 1.14), respectively (P < 0.01). Strips from control and sensitized animals at each site and strips from different generations did not show any significant difference. When we clustered our preparations according to dimensions, the response to histamine was significantly higher in small bronchi than in large ones and histamine EC50 was 8.95 x 10(-6) (GSEM 1.17) and 1.57 x 10(-5) M (GSEM 1.18), respectively (P < 0.05). We conclude that evaluation of muscle response in different tissues requires appropriate normalization. Furthermore, classification into generations is inadequate to study bronchial responsiveness, inasmuch as major differences originate from airway size.

Gender differences in upper airway compliance during NREM sleep: role of neck circumference

2002 ◽  
Vol 92 (6) ◽  
pp. 2535-2541 ◽  
Author(s):  
James A. Rowley ◽  
Carrie S. Sanders ◽  
Brian R. Zahn ◽  
M. Safwan Badr
Keyword(s):  
Gender Differences ◽  
Gender Difference ◽  
Upper Airway ◽  
Nrem Sleep ◽  
Neck Circumference ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Significant Difference ◽  
Upper Airway Structure

It has been proposed that the gender difference in sleep apnea prevalence is related to gender differences in upper airway structure and function. We hypothesized that men would have smaller retropalatal cross-sectional area and higher compliance during sleep compared with women. Using upper airway imaging, we measured upper airway cross-sectional area and retropalatal compliance in wakefulness and non-rapid eye movement (NREM) sleep in 15 men and 15 women without sleep-disordered breathing. Cross-sectional area at the beginning of inspiration tended to be larger in men compared with women in both wakefulness [194.5 ± 21.3 vs. 138.8 ± 12.0 (SE) mm2] and NREM sleep (111.1 ± 17.6 vs. 83.3 ± 11.9 mm2; P = 0.058). There was no significant difference, however, after correction for body surface area. Retropalatal compliance also tended to be higher in men during both wakefulness (5.9 ± 1.4 vs. 3.1 ± 1.4 mm2/cmH2O; P = 0.006) and NREM sleep (12.6 ± 2.7 vs. 4.7 ± 2.6 mm2/cmH2O; P = 0.055). However, compliance was similar in men relative to women after correction for neck circumference. We conclude that the gender difference in retropalatal compliance is more accurately attributed to differences in neck circumference between the genders.

The Effect of ACL Reconstruction on Involved and Contralateral Limb Vastus Lateralis Morphology and Histology: A Pilot Study

2019 ◽  
Author(s):  
Eric C. Leszczynski ◽  
Christopher Kuenze ◽  
Brett Brazier ◽  
Joseph Visker ◽  
David P. Ferguson
Keyword(s):  
Fiber Type ◽  
Vastus Lateralis ◽  
Knee Extension ◽  
Cross Sectional Area ◽  
Vastus Lateralis Muscle ◽  
Myosin Isoforms ◽  
Sectional Area ◽  
Cross Sectional ◽  
Contralateral Limb ◽  
Significant Difference

AbstractQuadriceps muscle weakness is a commonly reported issue post anterior cruciate ligament reconstruction (ACLR), with minimal information related to skeletal muscle morphology following surgery. The purpose is to examine the morphological and functional differences in the vastus lateralis muscle from patient's ACLR and contralateral leg. Three physically active ACLR participants were recruited and secured to a dynamometer to perform maximal voluntary isometric knee extension contractions (MVIC) of the ACLR and contralateral limb. Muscle biopsies of the ACLR and contralateral vastus lateralis were performed, then sectioned, and stained for myosin isoforms to determine fiber type. Confocal images were acquired, and ImageJ software was used to determine the fiber type and cross-sectional area (CSA). There was a significant reduction in CSA of the type IIa and type IIx muscle fiber cells between healthy (IIa: 7,718 ± 1,295 µm2; IIx; 5,800 ± 601 µm2) and ACLR legs (IIa: 4,139 ± 709 µm2; IIx: 3,708 ± 618 µm2) (p < 0.05), while there was no significant difference in knee extension MVIC torque between legs (healthy limb: 2.42 ± 0.52 Nm/kg; ACLR limb: 2.05 ± 0.24 Nm/kg, p = 0.11). The reduction in the cross-sectional area of the ACLR type II fibers could impair function and increase secondary injury risk.

scholarly journals Soleus fiber force and maximal shortening velocity after non-weight bearing with intermittent activity

1996 ◽  
Vol 80 (3) ◽  
pp. 981-987 ◽  
Author(s):  
J. J. Widrick ◽  
J. J. Bangart ◽  
M. Karhanek ◽  
R. H. Fitts
Keyword(s):  
Isometric Force ◽  
Weight Bearing ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cross Sectional Area ◽  
Type I ◽  
Sectional Area ◽  
Shortening Velocity ◽  
Adult Rats ◽  
Cross Sectional

This study examined the effectiveness of intermittent weight bearing (IWB) as a countermeasure to non-weight-bearing (NWB)-induced alterations in soleus type I fiber force (in mN), tension (Po; force per fiber cross-sectional area in kN/m-2), and maximal unloaded shortening velocity (Vo, in fiber lengths/s). Adult rats were assigned to one of the following groups: normal weight bearing (WB), 14 days of hindlimb NWB (NWB group), and 14 days of hindlimb NWB with IWB treatments (IWB group). The IWB treatment consisted of four 10-min periods of standing WB each day. Single, chemically permeabilized soleus fiber segments were mounted between a force transducer and position motor and were studied at maximal Ca2+ activation, after which type I fiber myosin heavy-chain composition was confirmed by sodium dodecyl sufate-polyacrylamide gel electrophoresis. NWB resulted in a loss in relative soleus mass (-45%), with type I fibers displaying reductions in diameter (-28%) and peak isometric force (-55%) and an increase in Vo (+33%). In addition, NWB induced a 16% reduction in type I fiber Po, a 41% reduction in type I fiber peak elastic modulus [Eo, defined as (delta force/delta length) x (fiber length/fiber cross-sectional area] and a significant increase in the Po/Eo ratio. In contrast to NWB, IWB reduced the loss of relative soleus mass (by 22%) and attenuated alterations in type I fiber diameter (by 36%), peak force (by 29%), and Vo (by 48%) but had no significant effect on Po, Eo, or Po/Eo. These results indicate that a modest restoration of WB activity during 14 days of NWB is sufficient to attenuate type I fiber atrophy and to partially restore type I peak isometric force and Vo to WB levels. However, the NWB-induced reductions in Po and Eo, which we hypothesize to be due to a decline in the number and stiffness of cross bridges, respectively, are considerably less responsive to this countermeasure treatment.

scholarly journals Radiographic Analysis of Glenoid Morphology after Arthroscopic Latarjet vs Distal Tibial Allograft in the Treatment of Anterior Shoulder Instability

2018 ◽  
Vol 6 (7_suppl4) ◽  
pp. 2325967118S0009 ◽  
Author(s):  
Ivan H. Wong ◽  
JP King ◽  
Gordon Boyd ◽  
Michael Mitchell ◽  
Catherine M. Coady
Keyword(s):  
Shoulder Instability ◽  
Distal Tibia ◽  
Cross Sectional Area ◽  
Anterior Shoulder Instability ◽  
Sectional Area ◽  
Common Procedure ◽  
Cross Sectional ◽  
Significant Difference ◽  
Glenoid Reconstruction ◽  
Graft Resorption

Objectives: The Latarjet procedure for autograft transposition of coracoid to the anterior rim of the glenoid remains the most common procedure for reconstruction of the glenoid after shoulder instability. The anatomic glenoid reconstruction using distal tibial allograft has gained popularity and is suggested to better match the normal glenoid size and shape. However, there is concern for decreased healing and increased resorption using an allograft bone. The purpose of this study was to evaluate the arthroscopic reconstruction of the glenoid with respect to the size, shape, healing, and resorption of autograft coracoid vs allograft distal tibia. Methods: A retrospective review of 50 consecutive patients who had an arthroscopic boney reconstruction of the glenoid (13 coracoid; 37 distal tibial), diagnosed with anterior shoulder instability, and CT confirmed glenoid bone loss >20%. Pre-and post-operative CT scans were reviewed by two fellowship trained musculoskeletal radiologists for: graft position, glenoid concavity, cross sectional area, width, version, total area, osseous union, and graft resorption. Results: Graft nonunion was seen in 3 (23.07%) of the coracoid patients, and in 2 (5.4%) of the tibial allograft patients (OR 5.25; 95% CI: 0.768-35.89). Odds ratios comparing allograft to coracoid for overall resorption was 5.00 (CI: 1.276-19.597). Graft resorption greater than 50% was seen in 3 (8.11%) of the allografts and was absent within the coracoid patients. Graft resorption lesser than 50% was greater in both groups with 27 (72.97%) allograft and 6 (46.15%) coracoid patients. However, no statistically significant difference was found between the two procedures regarding AP diameter of graft (p=0.818) or graft cross sectional area (p=0.797). Conclusion: Arthroscopic anatomic glenoid reconstruction using distal tibial allograft showed greater boney union but higher resorption compared to coracoid autograft. Even so, there was no statistically significant difference between the two procedures regarding final graft surface area and size of grafts. These short-term results suggest distal tibial allograft as an alternative to coracoid autograft in the recreation of glenoid boney morphology.

Infraspinatus Cross-Sectional Area and Shoulder Range of Motion Change Following Live-Game Baseball Pitching

2019 ◽  
Vol 28 (3) ◽  
pp. 236-242 ◽  
Author(s):  
Brett S. Pexa ◽  
Eric D. Ryan ◽  
Elizabeth E. Hibberd ◽  
Elizabeth Teel ◽  
Terri Jo Rucinski ◽  
...  
Keyword(s):  
Range Of Motion ◽  
Athletic Training ◽  
Repeated Measures ◽  
External Rotation ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Shoulder Range Of Motion ◽  
Posterior Shoulder ◽  
Before And After

Context: Following a baseball pitching bout, changes can occur to glenohumeral range of motion that could be linked to injury. These effects are in part due to the posterior shoulder’s eccentric muscle activity, which can disrupt muscle contractile elements and lead to changes in muscle cross-sectional area (CSA), as measured by ultrasound. Objective: To assess changes in muscle CSA, and range of motion immediately before and after pitching, and days 1 to 5 following pitching. Design: Repeated measures. Setting: Satellite athletic training room. Patients: Ten elite college baseball pitchers participating in the fall season (age: 18.8 [1.2] y, height: 189.2 [7.3] cm, mass: 93.1 [15.3] kg, 8 starters, 2 long relievers). Intervention: A pitching bout of at least 25 pitches (63.82 [17.42] pitches). Main Outcome Measures: Dominant and nondominant infraspinatus CSA, as measured by ultrasound, and glenohumeral range of motion including internal rotation (IRROM), external rotation (ERROM), and total rotation range of motion (TROM) before pitching, after pitching, and days 1 to 5 following the pitching bout. Results: Dominant limb CSA significantly increased day 1 after pitching, and returned to baseline on day 2 (P < .001). Dominant and nondominant TROM did not change until day 5 (4.4°, P < .001) and day 3 (4.5°, P < .001), respectively, where they increased. Dominant IRROM was significantly decreased for 3 days (day 1: 1.9°, P < .001; day 2: 3.1°, P < .001; day 3: 0.3°, P < .001) following pitching and returned to baseline on day 4, with no such changes in the nondominant limb. Dominant external rotation significantly increased immediately post pitching (4.4°, P < .001) but returned to baseline by day 1. Conclusions: The results of the study demonstrate that infraspinatus CSA does not recover until 2 days following pitching, and IRROM does not recover until 4 days following pitching. Baseball pitching elicits damage to the posterior shoulder muscle architecture, resulting in changes to physical characteristics that last up to 4 days following pitching.

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