Does Exercise Type Affect Relative Activation Levels of Vastus Medialis Oblique and Vastus Laterialis?

2006 ◽  
Vol 15 (4) ◽  
pp. 271-279 ◽  
Author(s):  
Lee Herrington ◽  
Stephen Pearson
Keyword(s):  
Outcome Measures ◽  
Repeated Measures ◽  
Vastus Medialis ◽  
Exercise Interventions ◽  
Factorial Anova ◽  
Onset Timing ◽  
Significant Difference ◽  
Research Findings ◽  
Exercise Type ◽  
Main Effects

Context:One factor believed to affect Patella tracking is an alteration in the timing of the contraction of the muscular stabilizers of the patella. The muscles responsible for this are Vastus Medialis Oblique (VMO) and Vastus Laterialis (VL). A number of authors believe that asynchronous recruitment of the VMO muscle occurs in patella mal-tracking, with the VL muscle firing first and VMO firing first with normal tracking. This has lead to a variety of exercise interventions to reverse the situation with varying success. The discrepancy between the majority of the available research findings and the clinical hypothesis of VMO action or facilitation of this action may in part be due to methodological variability between studies, especially lack of control of the exercise variables of angular velocity and relative load.Objective:To assess the effect of different quadriceps exercises on VMO and VL EMG recruitment timing, while controlling load and velocity of contraction.Design:Repeated measures.Setting:Biomechanics laboratory.Main Outcome Measures:Differences in time of onset of muscle activity between VMO and VL.Results:No significant difference existed between gender (P= 0.78). Analysis factorial ANOVA (muscle, contraction type and exercise type) showed the main effects of muscle (P= 0.15) and type of contraction (P= 0.79) did not have a significant effect, the nature of exercise (OKC or CKC) had a significant effect (P< 0.001). The interaction of muscle and exercise type (P= 0.34) also had a nonsignificant effect.Conclusions:Onset timing does not differ significantly between VMO and VL during a variety of exercise tasks.

scholarly journals The Effect of Pedal Pump Lymphatic Technique Versus Passive Recovery Following Maximal Exercise: A Randomized Cross-Over Trial

2022 ◽  
Vol 8 (1) ◽  
Author(s):  
Joanne DiFrancisco-Donoghue ◽  
Thomas Chan ◽  
Alexandra S. Jensen ◽  
James E. B. Docherty ◽  
Rebecca Grohman ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Maximal Exercise ◽  
Lactate Concentration ◽  
The Body ◽  
Intense Exercise ◽  
Passive Recovery ◽  
Significant Difference ◽  
Recovery Protocols

Abstract Context Muscle damage and delayed onset muscle soreness (DOMS) can occur following intense exercise. Various modalities have been studied to improve blood lactate accumulation, which is a primary reason for DOMS. It has been well established that active recovery facilitates blood lactate removal more rapidly that passive recovery due to the pumping action of the muscle. The pedal pump is a manual lymphatic technique used in osteopathic manipulative medicine to increase lymphatic drainage throughout the body. Pedal pump has been shown to increase lymphatic flow and improve immunity. This may improve circulation and improve clearance of metabolites post-exercise. Objective This study compared the use of pedal pump lymphatic technique to passive supine recovery following maximal exercise. Methods 17 subjects (male n = 10, age 23 ± 3.01; female n = 7, age 24 ± 1.8), performed a maximal volume O2 test (VO2 max) using a Bruce protocol, followed by a recovery protocol using either pedal pump technique or supine passive rest for 10 min, followed by sitting for 10 min. Outcome measures included blood lactate concentration (BL), heart rate (HR), systolic blood pressure (SBP) and VO2. Subjects returned on another day to repeat the VO2 max test to perform the other recovery protocol. All outcomes were measured at rest, within 1- minute post-peak exercise, and at minutes 4, 7, 10 and 20 of the recovery protocols. A 2 × 6 repeated measures ANOVA was used to compare outcome measures (p ≤ 0.05). Results No significant differences were found in VO2, HR, or SBP between any of the recovery protocols. There was no significant difference in BL concentrations for recovery at minutes 4, 7, or 10 (p > 0.05). However, the pedal pump recovery displayed significantly lower BL concentrations at minute 20 of recovery (p = 0.04). Conclusion The pedal pump significantly decreased blood lactate concentrations following intense exercise at recovery minute 20. The use of manual lymphatic techniques in exercise recovery should be investigated further.

Comparing the Effects of Peroneal Muscle Fatigue and Cyclic Loading on Ankle Neuromuscular Control During Lateral-Hop Landing

2015 ◽  
Vol 24 (3) ◽  
pp. 293-299 ◽  
Author(s):  
Kazem Malmir ◽  
Gholam Reza Olyaei ◽  
Saeed Talebian ◽  
Ali Ashraf Jamshidi
Keyword(s):  
Reaction Time ◽  
Muscle Fatigue ◽  
Energy Absorption ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Neuromuscular Control ◽  
Median Frequency ◽  
Peroneus Longus ◽  
Significant Difference ◽  
Main Effect

Context:Cyclic movements and muscle fatigue may result in musculoskeletal injuries by inducing changes in neuromuscular control. Ankle frontal-plane neuromuscular control has rarely been studied in spite of its importance.Objective:To compare the effects of peroneal muscle fatigue and a cyclic passive-inversion (CPI) protocol on ankle neuromuscular control during a lateral hop.Design:Quasi-experimental, repeated measures.Setting:University laboratory.Participants:22 recreationally active, healthy men with no history of ankle sprain or giving way.Interventions:Participants performed a lateral hop before and after 2 interventions on a Biodex dynamometer. They were randomly assigned to intervention order and interventions were 1 wk apart. A passive intervention included 40 CPIs at 5°/s through 80% of maximum range of motion, and a fatigue intervention involved an isometric eversion at 40% of the maximal voluntary isometric contraction until the torque decreased to 50% of its initial value.Main Outcome Measures:Median frequency of the peroneus longus during the fatigue protocol, energy absorption by the viscoelastic tissues during the CPI protocol, and feedforward onset and reaction time of the peroneus longus during landing.Results:A significant fall in median frequency (P < .05) and a significant decrease in energy absorption (P < .05) confirmed fatigue and a change in viscoelastic behavior, respectively. There was a significant main effect of condition on feedforward onset and reaction time (P < .05). No significant main effect of intervention or intervention × condition interaction was noted (P > .05). There was a significant difference between pre- and postintervention measures (P < .0125), but no significant difference was found between postintervention measures (P > .0125).Conclusions:Both fatigue and the CPI may similarly impair ankle neuromuscular control. Thus, in prolonged sports competitions and exercises, the ankle may be injured due to either fatigue or changes in the biomechanical properties of the viscoelastic tissues.

Investigating the Impact of Auditor-Provided Systems Reliability Assurance on Potential Service Recipients (Retracted)

2002 ◽  
Vol 16 (s-1) ◽  
pp. 69-87 ◽  
Author(s):  
J. Efrim Boritz ◽  
James E. Hunton
Keyword(s):  
Firm Size ◽  
Comfort Level ◽  
Significant Difference ◽  
Assurance Services ◽  
Research Findings ◽  
Upper Level ◽  
Functional Areas ◽  
Main Effects ◽  
The Impact ◽  
Variance Explained

The objective of this study is to assess the extent to which auditor-provided systems reliability assurance affects potential service recipients' (1) likelihood of recommending that their company enter into a contractual agreement with the service provider, and (2) comfort level with the reliability of the service provider's information systems. We conducted a full-factorial between-subjects experiment where the following four auditor assurances were either absent or present: availability, security, integrity, and maintainability. A total of 481 middle- and upper-level managers from a broad spectrum of functional areas participated in the study. Research findings indicate significant main effects with respect to all four assurances, as well as firm size, for the “likelihood” variable. Significant main effects were also obtained for the “comfort” variable with respect to availability, security, and maintainability (marginal significance), but integrity and firm size were nonsignificant. The amount of variance explained by the “availability” and “security” assurances (combined) was remarkably large (56 percent for “likelihood” and 43 percent for “comfort”) relative to the combined variance explained by the other two assurances (1 percent for “likelihood” and 1 percent for “comfort”). We also found evidence that respondents overweighed assurance reports on individual principles, as compared to a four-principle reliability report. Additionally, we found no significant difference in dependent variable responses when all four assurances were provided and the auditor's report focused on either the (1) effectiveness of controls or (2) reliability of the system. Research evidence offers key strategic guidance to the AICPA, CICA, and CPA/CA firms engaged in systems reliability assurance services.

Comparison of Hip- and Back-Muscle Activity and Pelvic Compensation in Healthy Subjects During 3 Different Prone Table Hip-Extension Exercises

2017 ◽  
Vol 26 (4) ◽  
pp. 216-222 ◽  
Author(s):  
In-cheol Jeon ◽  
Oh-yun Kwon ◽  
Jong-hyuck Weon ◽  
Ui-jae Hwang ◽  
Sung-hoon Jung
Keyword(s):  
Outcome Measures ◽  
Muscle Activity ◽  
Repeated Measures ◽  
Motion Tracking ◽  
Gluteus Maximus ◽  
Biceps Femoris ◽  
Erector Spinae ◽  
Repeated Measure ◽  
Significant Difference ◽  
Hip Extension

Context:Prone hip extension has been recommended for strengthening the back and hip muscles. Previous studies have investigated prone hip extension conducted with subjects on the floor in the prone position. However, no study has compared 3 different table hip-extension (THE) positions in terms of the activities of the back- and hip-joint muscles with lumbopelvic motion.Objective:To identify more effective exercises for strengthening the gluteus maximus (GM) by comparing 3 different exercises (THE alone, THE with the abdominal drawing-in maneuver [THEA], and THEA with chair support under the knee [THEAC]) based on electromyographic muscle activity and pelvic compensation.Design:Repeated-measure within-subject intervention.Setting:University research laboratory.Participants:16 healthy men.Main Outcome Measures:Surface electromyography (EMG) was used to obtain data on the GM, erector spinae (ES), multifidus, biceps femoris (BF), and semitendinosus (ST). Pelvic compensation was monitored using an electromagnetic motion-tracking device. Exertion during each exercise was recorded. Any significant difference in electromyographic muscle activity and pelvic motion among the 3 conditions (THE vs THEA vs THEAC) was assessed using a 1-way repeated-measures analysis of variance (ANOVA) with Bonferroni post hoc test.Results:The muscle activities recorded by EMG differed significantly among the 3 exercises (P < .01). GM activity was increased significantly during THEAC (P < .01). There was a significant difference in lumbopelvic kinematics in terms of anterior tilting (F = 19.49, P < .01) and rotation (F= 27.38, P < .01) among the 3 exercises.Conclusions:The THEAC exercise was the most effective for strengthening the GM without overactivity of the ES, BF, and ST muscles and lumbopelvic compensation compared with THE and THEA.

Shoulder-Rotator Strength of High School Swimmers Over the Course of a Competitive Season

2004 ◽  
Vol 13 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Martin Ramsi ◽  
Kathleen A. Swanik ◽  
Charles “Buz” Swanik ◽  
Steve Straub ◽  
Carl Mattacola
Keyword(s):  
High School ◽  
Outcome Measures ◽  
Repeated Measures ◽  
Type Design ◽  
Competitive Season ◽  
Male High School ◽  
Males And Females ◽  
Main Effects ◽  
Competitive Swimmers ◽  
External Rotator

Context:Changes in strength over the course of a swim season could predispose the shoulder to strength imbalances and lead to injury.Objective:To examine isometric shoulder internal- (IR) and external-rotator (ER) strength in high school swimmers over a 12-week competitive season.Design:Three 3 × 2 × 2 ANOVAs with repeated measures were used to determine significant main effects for IR, ER, and IR:ER strength ratio.Participants:27 (14 female, 13 male) high school varsity swimmers.Main Outcome Measures:IR and ER strength during preseason, midseason, and postseason.Results:Significant increases in IR strength in both groups were revealed for all test sessions. ER strength significantly improved in both males and females from preseason to midseason and from preseason to postseason. IR:ER ratio revealed a significant increase from preseason to postseason.Conclusions:Increases in IR strength without equal gains in ER strength were revealed and could contribute to future shoulder pathologies in competitive swimmers

A Comparison of Intramuscular Temperatures during 10-Minute 1.0-MHz Ultrasound Treatments at Different Intensities

2004 ◽  
Vol 13 (3) ◽  
pp. 244-254 ◽  
Author(s):  
Jamie Leonard ◽  
Mark Merrick ◽  
Chris Ingersoll ◽  
Mitchell Cordova
Keyword(s):  
Outcome Measures ◽  
Repeated Measures ◽  
Latin Square ◽  
Triceps Surae ◽  
Variable Intensity ◽  
Thermal Change ◽  
Significant Difference ◽  
Independent Variable ◽  
Treatment Order ◽  
Intramuscular Temperature

Context:Research on therapeutic ultrasound has not focused on the duration needed to cause thermal change with various ultrasound intensities.Objective:To analyze triceps surae intramuscular temperature using 4 intensity levels after a 10-min 1-MHz continuous ultrasound treatment at a depth of 4 cm.Design:1 × 4 repeated measures. Independent variable: intensity of 4 levels—0.5, 1.0, 1.5, and 2.0 W/cm2. Dependent variable: peak intramuscular temperature.Setting:Research laboratory.Participants:19 volunteers with no lower leg pathologies.Intervention:Treatment order was balanced via Latin square and performed 24 hr apart.Main Outcome Measures:Peak intramuscular temperatures.Results:The only significant difference detected was that the mean temperature after the 1.0-W/cm2 treatment (37.3 °C) was greater than that at 2.0-W/cm2 intensity (36.1 °C). No treatment reached the desired 4° increase needed for therapeutic efficacy.Conclusions:Treatments at 1.0 W/cm2 increased tissue temperatures more than those at 2.0 W/cm2.

scholarly journals Kinematic and Electromyographic Activity Changes during Back Squat with Submaximal and Maximal Loading

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Hasan U. Yavuz ◽  
Deniz Erdag
Keyword(s):  
Repeated Measures ◽  
Injury Risk ◽  
Vastus Lateralis ◽  
Knee Extensor ◽  
Gluteus Maximus ◽  
Movement Pattern ◽  
Erector Spinae ◽  
Electromyographic Activity ◽  
Vastus Medialis ◽  
Significant Difference

The aim of this study was to investigate the possible kinematic and muscular activity changes with maximal loading during squat maneuver. Fourteen healthy male individuals, who were experienced at performing squats, participated in this study. Each subject performed squats with 80%, 90%, and 100% of the previously established 1 repetition maximum (1RM). Electromyographic (EMG) activities were measured for the vastus lateralis, vastus medialis, rectus femoris, semitendinosus, biceps femoris, gluteus maximus, and erector spinae by using an 8-channel dual-mode portable EMG and physiological signal data acquisition system (Myomonitor IV, Delsys Inc., Boston, MA, USA). Kinematical data were analyzed by using saSuite 2D kinematical analysis program. Data were analyzed with repeated measures analysis of variance (p<0.05). Overall muscle activities increased with increasing loads, but significant increases were seen only for vastus medialis and gluteus maximus during 90% and 100% of 1RM compared to 80% while there was no significant difference between 90% and 100% for any muscle. The movement pattern in the hip joint changed with an increase in forward lean during maximal loading. Results may suggest that maximal loading during squat may not be necessary for focusing on knee extensor improvement and may increase the lumbar injury risk.

Alterations in Peak Ground-Reaction Force During 60-cm Drop Landings Caused by a Single Session of Repeated Wingate Anaerobic Tests

2012 ◽  
Vol 21 (4) ◽  
pp. 306-312 ◽  
Author(s):  
David J Dominguese ◽  
Jeff Seegmiller ◽  
B. Andrew Krause
Keyword(s):  
Muscle Fatigue ◽  
Outcome Measures ◽  
Ground Reaction Force ◽  
Repeated Measures ◽  
Reaction Force ◽  
Lower Extremity Injury ◽  
Single Session ◽  
Drop Landing ◽  
Significant Difference ◽  
Drop Landings

Context:Lower extremity injury is prevalent among individuals participating in sports. Numerous variables have been reported as predisposing risk factors to injury; however, the effects of muscle fatigue on landing kinetics are unclear.Objectives:To investigate the effects of a single session of repeated muscle fatigue on peak vertical ground-reaction force (GRF) during drop landings.Design:Mixed factorial with repeated measures.Setting:Controlled laboratory.Participants:10 female and 10 male healthy recreational athletes.Intervention:Subjects performed 3 fatigued drop landings (60 cm) after four 20-s Wingate anaerobic tests (WATs) with 5 min of active recovery between fatigued conditions.Main Outcome Measures:Kinetic data of peak forefoot (F1) force, peak rear-foot (F2) force, and anteroposterior (AP) and mediolateral (ML) forces at both F1 and F2.Results:A significant main effect was observed in the nonfatigued and fatigued drop landings in respect to peak F2 force. The greatest significant difference was shown between the first fatigued drop-landing condition and the last fatigued drop-landing condition. No significant difference was observed between genders for all GRF variables across fatigue conditions.Conclusion:A single session of repeated conditions of anaerobic muscle fatigue induced by WATs caused an initial reduction in peak F2 force followed by an increase in peak F2 force across conditions. Muscle fatigue consequently alters landing kinetics, potentially increasing the risk of injury.

Measurement of Ankle Dorsiflexion: A Comparison of Active and Passive Techniques in Multiple Positions

2011 ◽  
Vol 20 (3) ◽  
pp. 333-344 ◽  
Author(s):  
David A. Krause ◽  
Beth A. Cloud ◽  
Lindsey A. Forster ◽  
Jennifer A. Schrank ◽  
John H. Hollman
Keyword(s):  
Outcome Measures ◽  
Repeated Measures ◽  
Interrater Reliability ◽  
Emg Activity ◽  
Minimal Detectable Change ◽  
Detectable Change ◽  
Intrarater Reliability ◽  
Significant Difference ◽  
Anterior Tibialis ◽  
Passive Techniques

Context:Limited ankle DF (DF) range of motion (ROM) resulting from restricted gastrocnemius and soleus mobility is associated with a variety of lower extremity pathologies. Several techniques are used clinically to measure ankle DF.Objectives:To evaluate the reliability and minimal detectable change of DF ROM measurement, determine whether there is a difference in measured DF between techniques, and quantify the electromyographic (EMG) activity of the soleus and tibialis anterior muscles associated with the techniques.Design:Repeated measures.Setting:Controlled laboratory setting.Participants:39 healthy subjects, age 22–33.Main Outcome Measures:DF measurements using 5 different techniques including active and passive DF with the knee extended and flexed to 90° and a modified lunge. EMG activity of the soleus and anterior tibialis muscles.Results:Intrarater reliability values (ICC3,1) ranged from .68 to .89. Interrater reliability (ICC2,1) ranged from .55 to .82. ICCs were the greatest with the modified lunge. The minimal detectable change (MDC95) ranged from 6° to 8° among the different techniques. A significant difference in DF ROM was found between all methods. Measurements taken with active DF were greater than the same measures taken passively. The lunge position resulted in greater DF ROM than both active and passive techniques. EMG activity of the soleus was greater with active DF and the lunge than with passive DF.Conclusions:The modified lunge, which demonstrated excellent intrarater and interrater reliability, may best represent maximal DF. Active end-range DF was significantly greater than passive end-range DF when measured at either 0° or 90° knee flexion. Greater active DF was not explained by inhibition of the soleus. Finally, using the modified lunge, a difference between 2 measurements over time of 6° or more suggests that a meaningful change has occurred.

scholarly journals Independent samples—more hypotheses testing

2021 ◽  
pp. 129-151
Author(s):  
Blaženka Knežević ◽  
Berislav Žmuk
Keyword(s):  
Analysis Of Variance ◽  
Hypotheses Testing ◽  
Factorial Anova ◽  
Significant Difference ◽  
Two Factors ◽  
Main Effects ◽  
Nominal Variables

Two-way analysis of variance (ANOVA) without replication is called a factorial ANOVA with two factors. It is used to test if there is a significant difference between means of several sets of data (groups) dependable on two independent factors. It is applied when we have one measurement variable and two nominal variables (usually called ‘factors’ or ‘main effects’). In this chapter hypotheses and assumptions of the method are given. Then the example of the procedure of two-way analysis of variance (ANOVA) without replication is described in details. The two-way analysis of variance (ANOVA) with replication is utilized to simultaneously test the effects of varying two variables for a sample which consists of more than one respondent per a certain combination of variables. The example of the procedure of two-way analysis of variance (ANOVA) with replication is described in details in this chapter. For both procedures the easy to follow examples shows the procedure stepby-step. The practical part includes the guidance for SPSS and for Excel.

Sign in / Sign up

Export Citation Format

Share Document