Dissociated time course between peak torque and total work recovery following bench press training in resistance trained men

AbstractThe present randomized controlled study aims to evaluate whether tourniquet application during total knee arthroplasty (TKA) has an effect on (1) thigh muscle strength (quadriceps and hamstring muscle strength) and (2) clinical outcomes (postoperative knee range of motion [ROM], postoperative pain level, and Knee Society Score [KSS]). The effects of tourniquet application during TKA were investigated in 65 patients randomly allocated to one of two groups: TKA with a tourniquet and TKA without a tourniquet. Patients in both groups were comparable in terms of the demographic and clinical data (p > 0.05 for age, number of patients, sex, radiographic gonarthrosis grade, American Society of Anesthesiologists [ASA] classification, and body mass index [BMI]). All patients in both groups were operated by the same surgeon using one type of prosthesis. Isokinetic muscle strength (peak torque and total work) of knee extensors (quadriceps) and flexors (hamstrings) was measured in Newton meters (Nm) using a CYBEX 350 isokinetic dynamometer (HUMAC/CYBEX 2009, Stoughton, MA). The combined KSS (knee score + function score), visual analog scale (VAS), and knee ROM were measured preoperatively and at 1 and 3 months postoperatively to evaluate clinical outcomes. There were no significant differences between the two groups in preoperative and postoperative values of isokinetic muscle strength (peak torque and total work) and aforementioned clinical outcomes (p < 0.05). The present study has shown that quadriceps strength and clinical outcomes were not improved in the early postoperative period (3 months) when a tourniquet was not used during TKA.

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Relationship between propulsive force of the arm, body composition and isokinetic muscle strength indicators in surfers

Brazilian Journal of Kinanthropometry and Human Performance ◽

10.5007/1980-0037.2018v20n3p342 ◽

2018 ◽

Vol 20 (3) ◽

pp. 342-351

Author(s):

Sidarta Oliveira Geber ◽

Bruno Remígio Cavalcante ◽

Antonio Henrique Germano-Soares ◽

Raysa Catarina Cavalcante Figueiredo Montes ◽

Arthur Henrique Oliveira Silva ◽

...

Keyword(s):

Body Composition ◽

Internal Rotation ◽

Fat Mass ◽

Muscle Function ◽

External Rotation ◽

Pearson Correlation ◽

Peak Torque ◽

Total Work ◽

Propulsive Force ◽

Teres Major

This study aimed to evaluate the potential relationship between body composition (percentage of fat mass (FM %), fat mass and lean mass), muscle function (e.g., muscles; deltoid side and front, pectoralis major and teres major) and the propulsive force of the arm (PFA). Sixteen competitive surfers (29.1 ± 7.3 years; 1.72 ± 0.06 m; 74.2 ± 1.4 kg) were assessed for height, body mass, body composition (dual-energy-DXA), muscle function and PFA. Pearson correlation analyses were used to verify the relationship between all variables. An inverse correlations were found between PFA and isokinetic parameters to 60o/s: external rotation (peak torque: r = -0.71; p = 0.014; total work: r = -0.75; p = 0.007; power: r = -0.72; p = 0.011) and internal rotation (peak torque: r = -0.61; p = 0.045; total work: r = -0.73; p = 0.010; power: r = -0.61; p = 0.045) and 300o/s: external rotation (peak torque: r = -0.79; p = 0.003; total work: r = -0.84; p<0,001; power: r = -0.81; p = 0.002) and internal rotation (peak torque: r = -0.69; p = 0.017; total work: r = -0.72; p = 0.011; power: r = -0.69; p = 0.017). There was no significant correlation between body composition components and PFA (p>0.05). Although correlations do not imply cause and effect, PFA is not correlated with body composition in surfers and these relationships are inversely related to the parameters of muscle function.

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Isokinetic Strength Profiles of Thigh Muscles of Modern Dancers in Relation to Their Experience Level

Medical Problems of Performing Artists ◽

10.21091/mppa.2013.3028 ◽

2013 ◽

Vol 28 (3) ◽

pp. 137-144

Author(s):

Ani Agopyan ◽

Demet Tekin ◽

Mehmet Unal ◽

Hizir Kurtel ◽

Gullu Turan ◽

...

Keyword(s):

Body Weight ◽

Peak Torque ◽

Thigh Muscle ◽

Isokinetic Strength ◽

Total Work ◽

Isokinetic Dynamometer ◽

Experience Level ◽

Strength Tests ◽

Angular Velocities ◽

Modern Dancers

The aim of this study was to determine maximal voluntary peak torque (PT), PT% body weight (PT%BW), total work (TW), and hamstring/quadriceps ratio (HQR) for bilateral and unilateral thigh muscle strength during isokinetic muscle contractions in modern dancers in relation to their experience level. METHODS: Twenty-two female dancers were divided into two groups: intermediate dancers (ID, n=11) and advanced dancers (AD, n=11). Strength tests were performed using the Biodex System-III Pro Multijoint System isokinetic dynamometer to determine three joint angular velocities (60, 180, 300°/s). RESULTS: During extension, ADs exhibited higher ratios in the HQR (p=0.016) on right leg at 300°/s, IDs generated greater TW (p=0.042), and within groups, there was a significant left-to-right difference in the HQR at 300°/s for ADs (p=0.042). During flexion, within groups, the ADs exhibited significant differences between legs for both PT (p=0.026) and PT%BW (p=0.022) at 300°/s. CONCLUSION: For both groups, the average HQR in all angular velocities was not within the recommended range, which is required to prevent injuries; at the same time, unilateral muscular imbalances existed. Lower extremities of ADs exhibited asymmetric strength patterns at a certain level. Further research should be done to confirm the findings of this pilot study.

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The Effect of Heating and Cooling on Time Course of Voluntary and Electrically Induced Muscle Force Variation

Medicina ◽

10.3390/medicina47010006 ◽

2011 ◽

Vol 47 (1) ◽

pp. 6 ◽

Cited By ~ 3

Author(s):

◽

Keyword(s):

Muscle Fatigue ◽

Time Course ◽

Muscle Force ◽

Peak Torque ◽

Voluntary Contraction ◽

Knee Extensors ◽

Lower Body ◽

Heating And Cooling ◽

Force Variation ◽

Voluntary Contractions

The aim of this study was to investigate the effect of heating and cooling on time course of voluntary and electrically induced muscle force variation. Material and Methods. Ten volunteers performed 50 maximal voluntary and electrically induced contractions of the knee extensors at an angle of 120 degrees under the control conditions and after passive lower body heating and cooling in the control, heating, and cooling experiments. Peak torque, torque variation, and half-relaxation time were assessed during the exercise. Results. Passive lower body heating increased muscle and core temperatures, while cooling lowered muscle temperature, but did not affect core temperature. We observed significantly lower muscle fatigue during voluntary contraction compared with electrically induced contractions. Body heating (opposite to cooling) increased involuntarily induced muscle force, but caused greater electrically induced muscle fatigue. In the middle of the exercise, the coefficient of correlation for electrically induced muscle torque decreased significantly as compared with the beginning of the exercise, while during maximal voluntary contractions, this relation for torque remained significant until the end of the exercise. Conclusion. It was shown that time course of voluntary contraction was more stable than in electrically induced contractions.

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Velocity-specific knee strength between professional and under-17 female volleyball player

South African Journal of Physiotherapy ◽

10.4102/sajp.v75i1.478 ◽

2019 ◽

Vol 75 (1) ◽

Author(s):

Alexandre R.M. Pelegrinelli ◽

Laís F. Dela Bela ◽

Mariana F. Silva ◽

Lucas C.R. Rodrigues ◽

João P. Batista ◽

...

Keyword(s):

Muscle Strength ◽

Knee Extensor ◽

Peak Torque ◽

Total Work ◽

Flexor Muscle ◽

Mean Power ◽

Cross Sectional ◽

Significant Group ◽

Surface Maps ◽

Volleyball Players

Background: Many studies have investigated isokinetic performance in volleyball players but not through surface maps.Objectives: The goals of this study were to assess velocity-specific isokinetic knee extensor–flexor muscle strength and to compare the isokinetic knee extensor–flexor muscles between professional (PRO) and under-17 (U17) female volleyball players.Method: This cross-sectional laboratory study was developed with two groups: PRO (n = 12), medianage = 21.3 years, and U17 (n = 9), medianage = 15 years. Peak torque, total work, mean power, angle of peak torque, hamstring–quadriceps torque ratio (H–Q ratio) and torque–angle–velocity surface maps were analysed from knee extension–flexion at 60, 120 and 300 degrees per second (°/s).Results: Significant differences were identified for extensor peak torque between PRO x = 202.3 Newton metre (N·m) (standard deviation [SD] = 24.4) and U17 x = 141.6 N·m (30.1) at 60 °/s (p < 0.001; d = 2.21) as well as flexor peak torque (PRO x = 75.7 N·m [10.3] and U17 x = 57.7 N·m [11.4]) at 120 °/s (p < 0.001; d = 1.65) for the dominant limb. There were also significant group differences for total work and mean power at all velocities for extension and flexion. Surface maps demonstrated higher torque at lower speeds for both groups with smaller torque changes across velocities for flexion.Conclusion: Different groups of female volleyball players showed contrasting concentric knee muscle strength across isokinetic velocities.Clinical implications: These results demonstrate the importance of specific strength training for different age groups, even within the same sport, and provide insight into muscle strength.

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Peak torque, total work and power values when comparing individuals with Q-angle differences

Isokinetics and Exercise Science ◽

10.3233/ies-2001-0060 ◽

2001 ◽

Vol 9 (1) ◽

pp. 27-30 ◽

Cited By ~ 4

Author(s):

Dana Binder ◽

Dawn Brown-Cross ◽

Eric Shamus ◽

George Davies

Keyword(s):

Peak Torque ◽

Total Work ◽

Q Angle

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Reliability of Isometric and Eccentric Isokinetic Shoulder External Rotation

Journal of Sport Rehabilitation ◽

10.1123/jsr.2015-0046 ◽

2016 ◽

Vol 25 (2) ◽

Cited By ~ 3

Author(s):

Brianna M. Papotto ◽

Thomas Rice ◽

Terry Malone ◽

Timothy Butterfield ◽

Tim L. Uhl

Keyword(s):

Repeated Measures ◽

External Rotation ◽

High Reliability ◽

Peak Torque ◽

Total Work ◽

Isokinetic Testing ◽

Deceleration Phase ◽

Shoulder Muscles ◽

Shoulder External Rotation ◽

Average Angle

Context: Shoulder external rotators are challenged eccentrically throughout the deceleration phase of throwing, which is thought to contribute to overuse injuries. To evaluate the effectiveness of intervention programs, as well as identifying deficits, reliable and responsive measures of isometric and eccentric shoulder external rotation are necessary. Previously, isometric measures have primarily tested a single position, and eccentric measures have not been found to have high reliability. Objective: To examine the between-days reliability of multiple-angle isometric and dynamic eccentric isokinetic testing of shoulder external rotation. Design: Repeated measures. Participants: 10 healthy subjects (age 30 ± 12 y, height 166 ± 13 cm, mass 72 ± 10 kg). Main Outcome Measures: Average isometric peak torque of shoulder external rotation at 7 angles was measured. From these values, the angle of isometric peak torque was calculated. Dynamic eccentric average peak torque, average total work, and average angle of peak torque were measured. Results: Between-days reliability was high for average peak torque during isometric contractions at all angles (ICC ≥ .85), as it was for dynamic eccentric average peak torque (ICC ≥ .97). The estimated angle of isometric peak torque (ICC ≤ .65) was not highly reliable between days. The average angle of peak torque from the eccentric testing produced inconsistent results. Average total work of dynamic eccentric shoulder external rotation was found to be highly reliable between days (ICC ≥ . 97). Conclusion: Aspects of force such as peak torque and total work in isometric and eccentric testing of the shoulder external-rotator muscles can be measured reliably between days and used to objectively evaluate shoulder strength and identify changes when they occur. Angle measurements of peak torque could provide insight into the mechanical properties of the posterior shoulder muscles but were found to be inconsistent between days.

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Absolute and Relative Endurance Parameters in Isokinetic Tests of Muscular Performance

Journal of Sport Rehabilitation ◽

10.1123/jsr.1.1.2 ◽

1992 ◽

Vol 1 (1) ◽

pp. 2-12 ◽

Cited By ~ 9

Author(s):

Pekka Kannus ◽

Lauren Cook ◽

Denise Alosa

Keyword(s):

Peak Torque ◽

Training Period ◽

Clinical Use ◽

Muscular Endurance ◽

Total Work ◽

Endurance Test ◽

Healthy Men ◽

Reference Parameter ◽

The Absolute ◽

Absolute Measurements

This study analyzed the normality and variability of the data outputs of isokinetic endurance parameters in 10 healthy men and 10 healthy women. The test consisted of 25 maximal reciprocal contractions of the hamstring and quadriceps muscles. In addition, half of the subjects underwent a 7-week training period after which the endurance test was repeated. The results showed that the consistency of the absolute endurance measurements (work performed during the last 5 repetitions [WL5] and total work during 25 repetitions [TW25] was equal to that of the reference parameter, the peak torque. In addition, the changes after 7 weeks training were very similar; values for all these parameters increased significantly. The relative endurance parameter (WL5/work during the first 5 repetitions) did not change due to training since both WL5 and WF5 improved approximately the same amount. In conclusion, the absolute measurements of muscular endurance can be recommended for clinical use, while the endurance index should not be used routinely.

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