scholarly journals Cooling of Lower Extremity Muscles According to Subcutaneous Tissue Thickness

2019 ◽  
Vol 54 (12) ◽  
pp. 1304-1307 ◽  
Author(s):  
Noelle M. Selkow

Context When using an ice bag, previous researchers recommended cooling times based on the amount of subcutaneous tissue. Unfortunately, many clinicians are unaware of these recommendations or whether they can be applied to other muscles. Objective To examine if muscles of the lower extremity cool similarly based on recommended cooling times. Design Crossover study. Setting Athletic training laboratory. Patients or Other Participants Fourteen healthy participants volunteered (8 men, 6 women; age = 21.1 ± 2.2 years, height = 174.2 ± 4.5 cm, weight = 74.0 ± 7.5 kg). Intervention(s) Subcutaneous tissue thickness was measured at the largest girth of the thigh, medial gastrocnemius, and medial hamstring. Participants were randomized to have either the rectus femoris or medial gastrocnemius and medial hamstring tested first. Using sterile techniques, the examiner inserted a thermocouple 1 cm into the muscle after accounting for subcutaneous tissue thickness. After the temperature stabilized, a 750-g ice bag was applied for 10 to 60 minutes to the area(s) for the recommended length of time based on subcutaneous adipose thickness (0 to 5 mm [10 minutes]; 5.5 to 10 mm (25 minutes]; 10.5 to 15 mm [40 minutes]; 15.5 to 20 mm [60 minutes)]. After the ice bag was removed, temperature was monitored for 30 minutes. At least 1 week later, each participant returned to complete testing of the other muscle(s). Main Outcome Measure(s) Intramuscular temperature (°C) at baseline, end of treatment time (0 minutes), and posttreatment recovery (10, 20, and 30 minutes postintervention). Results At the end of treatment, temperature did not differ by subcutaneous tissue thickness (10 minutes = 29.0°C ± 3.8°C, 25 minutes = 28.7°C ± 3.2°C, 40 minutes = 28.7°C ± 6.0°C, 60 minutes = 30.0°C ± 2.9°C) or muscle (rectus femoris = 30.1°C ± 3.8°C, gastrocnemius = 28.6°C ± 5.4°C, hamstrings = 28.1°C ± 2.5°C). No significant interaction was present for subcutaneous tissue thickness or muscle (P ≥ .126). Conclusions Lower extremity muscles seemed to cool similarly based on the recommended cooling times for subcutaneous tissue thickness. Clinicians should move away from standardized treatment times and adjust the amount of cooling time by ice-bag application based on subcutaneous tissue thickness.

2014 ◽  
Vol 41 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Brianna M. Millard ◽  
John A. Mercer

AbstractThe purpose of this study was to describe lower extremity muscle activity during the lacrosse shot. Participants (n=5 females, age 22±2 years, body height 162.6±15.2 cm, body mass 63.7±23.6 kg) were free from injury and had at least one year of lacrosse experience. The lead leg was instrumented with electromyography (EMG) leads to measure muscle activity of the rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), and medial gastrocnemius (GA). Participants completed five trials of a warm-up speed shot (Slow) and a game speed shot (Fast). Video analysis was used to identify the discrete events defining specific movement phases. Full-wave rectified data were averaged per muscle per phase (Crank Back Minor, Crank Back Major, Stick Acceleration, Stick Deceleration). Average EMG per muscle was analyzed using a 4 (Phase) x 2 (Speed) ANOVA. BF was greater during Fast vs. Slow for all phases (p<0.05), while TA was not influenced by either Phase or Speed (p>0.05). RF and GA were each influenced by the interaction of Phase and Speed (p<0.05) with GA being greater during Fast vs. Slow shots during all phases and RF greater during Crank Back Minor and Major as well as Stick Deceleration (p<0.05) but only tended to be greater during Stick Acceleration (p=0.076) for Fast vs. Slow. The greater muscle activity (BF, RF, GA) during Fast vs. Slow shots may have been related to a faster approach speed and/or need to create a stiff lower extremity to allow for faster upper extremity movements.


2020 ◽  
Vol 29 (8) ◽  
pp. 1093-1099
Author(s):  
Michelle A. Sandrey ◽  
Yu-Jen Chang ◽  
Jean L. McCrory

Context: Lower-extremity stress fractures (SFx) are a common occurrence during load-bearing activities of jumping and landing. To detect biomechanical changes during jumping postinjury, a fatigue model could be used. Objective: To evaluate muscle activation in the lower leg and tibial accelerations (TAs) prefatigue to postfatigue following a jumping task in those with and without a history of SFx. Design: Repeated-measures. Setting: Athletic Training Research Lab. Participants: A total of 30 active college-aged students with and without a history of lower-extremity (leg or foot) SFx (15 males and 15 females; 21.5 [5.04] y, height = 173.5 [12.7] cm, weight = 72.65 [16.4] kg). Intervention: A maximal vertical jump on one leg 3 times with arms folded across the chest prefatigue to postfatigue was performed. Fatigue protocol was standing heel raises on a custom-built platform at a pace controlled by a metronome until task failure was reached. Legs were tested using a randomized testing order. Electromyographic (EMG) surface electrodes were placed on the medial gastrocnemius, soleus, and tibialis anterior following a standardized placement protocol. A triaxial accelerometer was attached to the proximal anteromedial surface of the tibia. Main Outcome Measures: Linear envelopes of the medial gastrocnemius, soleus, and tibialis anterior and peak accelerations (resultant acceleration takeoff and landing). Results: Significant interaction for leg × test for tibialis anterior with a posttest difference between SFx and control (P = .05). There were decreases in EMG linear envelope following fatigue for medial gastrocnemius (P < .01) and tibialis anterior (P = .12) pretest to posttest. At takeoff, TA was greater in the SFx contralateral leg in comparison with the control leg (P = .04). At landing, TA was greater in posttest (P < .01) and in the SFx leg compared with SFx contralateral (P = .14). Conclusion: A decrease in muscle activity and an increase in TA following fatigue were noted for all subjects but especially for those with a history of SFx.


2008 ◽  
Vol 17 (1) ◽  
pp. 68-75 ◽  
Author(s):  
Michael G. Miller ◽  
Christopher C. Cheatham ◽  
William R. Holcomb ◽  
Rosealin Ganschow ◽  
Timothy J. Michael ◽  
...  

Context:No direct research has been conducted on the relationship between subcutaneous tissue thickness and neuromuscular electrical stimulation (NMES).Objective:The purpose of this study was to determine the effects of subcutaneous tissue thickness on NMES amplitude and NMES force production of the quadriceps.Design:Simple fixed design, testing the independent variable of subcutaneous thickness (skinfold) groups with the dependent variables of NMES amplitude and force production.Setting:Athletic Training Laboratory.Participants:29 healthy women.Intervention:NMES to produce at least 30% of maximal voluntary isometric contractions (MVIC) of the quadriceps.Main Outcome Measure:Maximal NMES amplitude and percentage of MVIC using NMES.Results:A significant skinfold category difference F2,28 = 3.92, P = .032 on NMES amplitude was found. Post hoc revealed the thinnest skinfold category tolerated less amplitude compared to the thickest category. A significant correlation was found between NMES amplitude skinfold category R = .557, P = .002.Conclusion:Higher NMES amplitudes are needed for the thickest skinfold category compared to the thinnest skinfold category.


2006 ◽  
Vol 15 (2) ◽  
pp. 105-115 ◽  
Author(s):  
Haydee G. Galvan ◽  
Amanda J. Tritsch ◽  
Richard Tandy ◽  
Mack D. Rubley

Context:Ice-bath temperatures range from 1 to 15ºC; the pain response during treatment might be temperature specific.Objective:To determine levels of perceived pain during ice-bath immersion at distinct temperatures.Design:2 (sex) × 3 (temperature) × 9 (treatment time).Setting:Athletic training research laboratory.Participants:32 healthy subjects.Intervention:Ankle immersion in 1, 10, and 15°C ice baths for 20 minutes.Main Outcome Measures:Discomfort measured by the Borg scale of perceived pain at immersion for 1, 2, 4, 6, 8, 10, 15, and 20 minutes.Results:The magnitude of pain felt depended on treatment temperature (F18,522= 11.65,P< .0001). Pain ratings were 43% higher for 1ºC than 10ºC and 70% higher than 15ºC, and ratings at 10ºC were 46% higher than at 15ºC.Conclusions:Pain depends on treatment temperature. Patients might report inconsistent pain ratings with varying temperature.


2014 ◽  
Vol 23 (2) ◽  
pp. 107-122 ◽  
Author(s):  
W. Matthew Silvers ◽  
Eadric Bressel ◽  
D. Clark Dickin ◽  
Garry Killgore ◽  
Dennis G. Dolny

Context:Muscle activation during aquatic treadmill (ATM) running has not been examined, despite similar investigations for other modes of aquatic locomotion and increased interest in ATM running.Objectives:The objectives of this study were to compare normalized (percentage of maximal voluntary contraction; %MVC), absolute duration (aDUR), and total (tACT) lower-extremity muscle activity during land treadmill (TM) and ATM running at the same speeds.Design:Exploratory, quasi-experimental, crossover design.Setting:Athletic training facility.Participants:12 healthy recreational runners (age = 25.8 ± 5 y, height = 178.4 ± 8.2 cm, mass = 71.5 ± 11.5 kg, running experience = 8.2 ± 5.3 y) volunteered for participation.Intervention:All participants performed TM and ATM running at 174.4, 201.2, and 228.0 m/min while surface electromyographic data were collected from the vastus medialis, rectus femoris, gastrocnemius, tibialis anterior, and biceps femoris.Main Outcome Measures:For each muscle, a 2 × 3 repeated-measures ANOVA was used to analyze the main effects and environment–speed interaction (P ≤ .05) of each dependent variable: %MVC, aDUR, and tACT.Results:Compared with TM, ATM elicited significantly reduced %MVC (−44.0%) but increased aDUR (+213.1%) and tACT (+41.9%) in the vastus medialis, increased %MVC (+48.7%) and aDUR (+128.1%) in the rectus femoris during swing phase, reduced %MVC (−26.9%) and tACT (−40.1%) in the gastrocnemius, increased aDUR (+33.1%) and tACT (+35.7%) in the tibialis anterior, and increased aDUR (+41.3%) and tACT (+29.2%) in the biceps femoris. At faster running speeds, there were significant increases in tibialis anterior %MVC (+8.6−15.2%) and tACT (+12.7−17.0%) and rectus femoris %MVC (12.1−26.6%; swing phase).Conclusion:No significant environment–speed interaction effects suggested that observed muscle-activity differences between ATM and TM were due to environmental variation, ie, buoyancy (presumed to decrease %MVC) and drag forces (presumed to increase aDUR and tACT) in the water.


Author(s):  
Kung-Shan Cheng ◽  
Robert B. Roemer

This study derives the first analytic solution for evaluating the optimal treatment parameters needed for delivering a desired thermal dose during thermal therapies consisting of a single heating pulse. Each treatment is divided into four time periods (two power-on and two power-off), and the thermal dose delivered during each of those periods is evaluated using the non-linear Sapareto and Dewey equation relating thermal dose to temperature and time. The results reveal that the thermal dose delivered during the second power-on period when T&gt;43C (TD2) and the initial power-off period when T&gt;43C (TD3) contribute the major portions of the total thermal dose needed for a successful treatment (taken as 240 CEM43°C), and that TD3 dominates for treatments with higher peak temperatures. For a fixed perfusion value, the analytical results show that once the maximum treatment temperature and the total thermal dose (e.g., 240 CEM43°C) are specified, then the required heating time and the applied power magnitude are uniquely determined. These are the optimal heating parameters since lower/higher values result in under-dosing/over-dosing of the treated region. It is also shown that higher maximum treatment temperatures result in shorter treatment times, and for each patient blood flow there is a maximum allowable temperature that can be used to reach the desired thermal dose. In addition, since TD2 and TD3 contribute most of the total thermal dose, and they are both significantly affected by the blood flow present for high treatment temperatures, these results show that perfusion effects must be considered when attempting to optimize high temperature thermal therapy treatments (no excess thermal dose delivered, minimum power applied and shortest treatment time attained).


Biomechanics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 202-213
Author(s):  
Harish Chander ◽  
Sachini N. K. Kodithuwakku Arachchige ◽  
Alana J. Turner ◽  
Reuben F. Burch V ◽  
Adam C. Knight ◽  
...  

Background: Occupational footwear and a prolonged duration of walking have been previously reported to play a role in maintaining postural stability. The purpose of this paper was to analyze the impact of three types of occupational footwear: the steel-toed work boot (ST), the tactical work boot (TB), and the low-top work shoe (LT) on previously unreported lower extremity muscle activity during postural stability tasks. Methods: Electromyography (EMG) muscle activity was measured from four lower extremity muscles (vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) during maximal voluntary isometric contractions (MVIC) and during a sensory organization test (SOT) every 30 min over a 4 h simulated workload while wearing ST, TB, and LT footwear. The mean MVIC and the mean and percentage MVIC during each SOT condition from each muscle was analyzed individually using a repeated measures ANOVA at an alpha level of 0.05. Results: Significant differences (p < 0.05) were found for maximal exertions, but this was limited to only the time main effect. No significant differences existed for EMG measures during the SOT. Conclusion: The findings suggest that occupational footwear type does not influence lower extremity muscle activity during both MVIC and SOT. Significantly lower muscle activity during maximal exertions over the course of the 4 h workload was evident, which can be attributed to localized muscular fatigue, but this was not sufficient to impact muscle activity during postural stability tasks.


2016 ◽  
Vol 29 (suppl 1) ◽  
pp. 8-11
Author(s):  
João Vicente Machado GROSSI ◽  
Felipe Fernandes NICOLA ◽  
Ivan Alberto ZEPEDA ◽  
Martina BECKER ◽  
Eduardo Neubarth TRINDADE ◽  
...  

ABSTRACT Background: The evaluation of collagen in the abdominal wall has been increasingly studied because of the relevance on collagen in the healing process after laparotomy. Aim: To evaluate the amount of collagen in the linea alba of patients undergoing laparotomic bariatric surgery and comparing with non-obese cadavers. Methods: Were evaluated 88 samples of aponeurosis from abdominal linea alba of 44 obese patients (obesity group) and 44 non-obese cadavers (control group). The samples were collected in 2013 and 2104, and were sorted according to age (18-30, 31-45 and 46-60), gender, BMI, waist and cervical circumference, and subcutaneous tissue thickness. Material for biopsy was collected from the supraumbilical region of the linea alba for immunohistochemical analysis differentiating collagen type 1 and type 3 and the 1/3 ratio. Image-Pro Plus pixel counting software was used to measure the amount of collagen. Results: The obesity group evidenced mean age 44.11±9.90 years; 18-30 age group had three (6.8%) obese individuals; 31-45 had 22 (50%) and 46-60 had 19 (43.1%). Females were present in 81.8% (n=36); BMI (kg/m²) was 48.81±6.5; waist circumference (cm) was 136.761±13.55; subcutaneous tissue thickness (cm) 4.873±0.916. Considering age groups, gender and BMI, there were statistical differences in all tests when compared with the cadavers. Conclusion: The amount of collagen in the linea alba above the umbilical region in the morbidly obese patients was smaller than in the non-obese cadavers in the same age group.


2013 ◽  
Vol 699 ◽  
pp. 735-741 ◽  
Author(s):  
Ambali Saka Abdulkareem ◽  
Edison Muzenda ◽  
Ayo Samuel Afolabi

Acid treatment is one of the cheapest techniques and least applicable processes in the recycling of used lubricating oils. In this work, the performance of sulphuric acid in the treatment used oil was studied. The effects of the critical treatment parameters (acid volume, concentration of the acid, treatment temperature, stirring time and treatment time) were investigated by varying one treatment parameter at a time and analysing metal content in the sample of the treated oil using atomic absorption spectrometry (ASS). Thereafter, an optimal solution was determined by the combination of the optimum values of each treatment parameters. The original conventional treatment parameter values, resulted in 13.2 ppm and thereafter was optimised to 11 ppm this showed a definite improvement in efficiency. This result is also comparable to other data obtained in previously studied work which employed the same conventional treatment parameters. The optimal solution is within 10% variation as compared the standard individual metal content which ranges 0-10 ppm.


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