Ability of Isokinetic Dynamometer to Predict Isotonic Knee Extension 1-Repetition Maximum

2020 ◽  
Vol 29 (5) ◽  
pp. 616-620
Author(s):  
Joseph B. Lesnak ◽  
Dillon T. Anderson ◽  
Brooke E. Farmer ◽  
Dimitrios Katsavelis ◽  
Terry L. Grindstaff
Keyword(s):  
Resistance Training ◽  
Knee Injury ◽  
Peak Torque ◽  
Knee Extension ◽  
Prediction Equation ◽  
Isokinetic Dynamometer ◽  
Physically Active ◽  
Repetition Maximum ◽  
Knee Rehabilitation ◽  
Torque Values

Context: Resistance training exercise prescription is often based on exercises performed at a percentage of a 1-repetition maximum (1RM). Following knee injury, there is no consensus when a patient can safely perform 1RM testing. Resistance training programs require the use of higher loads, and loads used in knee injury rehabilitation may be too low to elicit gains in strength and power. A maximum isometric contraction can safely be performed during early stages of knee rehabilitation and has potential to predict an isotonic knee extension 1RM. Objective: To determine whether a 1RM on an isotonic knee extension machine can be predicted from isometric peak torque measurements. Design: Descriptive laboratory study. Setting: University research laboratory. Participants: A total of 20 (12 males and 8 females) healthy, physically active adults. Main Outcome Measures: An isokinetic dynamometer was used to determine isometric peak torque (in N·m). 1RM testing was performed on a knee extension machine. Linear regression was used to develop a prediction equation, and Bland–Altman plots with limits of agreement calculations were used to validate the equation. Results: There was a significant correlation (P < .001, r = .926) between peak torque (283.0 [22.6] N·m) and the knee extension 1RM (69.1 [22.6] kg). The prediction equation overestimated the loads (2.3 [9.1] kg; 95% confidence interval, −15.6 to 20.1 kg). Conclusions: The results show that isometric peak torque values obtained on an isokinetic dynamometer can be used to estimate 1RM values for isotonic knee extension. Although the prediction equation tends to overestimate loads, the relatively wide confidence intervals indicate that results should be viewed with caution.

scholarly journals Does Photobiomodulation Therapy Enhance Maximal Muscle Strength and Muscle Recovery?

2020 ◽  
Vol 73 (1) ◽  
pp. 135-144 ◽  
Author(s):  
Sharon Tsuk ◽  
Yarden Har Lev ◽  
Orly Fox ◽  
Rafael Carasso ◽  
Ayelet Dunsky
Keyword(s):  
Peak Torque ◽  
Placebo Treatment ◽  
Knee Extension ◽  
Isokinetic Dynamometer ◽  
Education Students ◽  
Muscle Recovery ◽  
Cell Functions ◽  
Physical Education Students ◽  
Double Blinded ◽  
Trial Participants

AbstractPhotobiomodulation has been shown to improve tissue and cell functions. We evaluated the influence of photobiomodulation, using a B-Cure laser, on: 1) maximal performance, and 2) muscle recovery after resistance exercise. Two separate crossover randomized double-blinded placebo-controlled trials were conducted. Sixty healthy physical education students (28 men, 32 women), aged 20-35, were recruited (30 participants for each trial). Participants performed two interventions for each experiment, with real lasers (GaAlAs, 808 nm) on three quadricep locations in parallel (overall treatment energy of ~150J) or sham (placebo) treatment. In the first experiment muscle total work (TW) and peak torque (PT) were measured by an isokinetic dynamometer in five repetitions of knee extension, and in the second experiment muscle recovery was measured after the induction of muscle fatigue by evaluating TW and PT in five repetitions of knee extension. There were no differences between treatments (real or sham) regarding the TW (F(1,28) = 1.09, p = .31), or PT (F(1,29) = .056, p = .814). In addition, there was no effect of photobiomodulation on muscle recovery as measured by the TW (F(1,27) = .16, p = .69) or PT (F(1,29) = .056, p = .814). Applying photobiomodulation for 10 min immediately before exercise did not improve muscle function or muscle recovery after fatigue.

scholarly journals Isokinetic assessment of knee flexor/extensor muscular strength in elderly women

2002 ◽  
Vol 57 (4) ◽  
pp. 131-134 ◽  
Author(s):  
Marcos de Amorim Aquino ◽  
Luiz Eugênio Garcez Leme ◽  
Marco Martins Amatuzzi ◽  
Júlia Maria D'Andréa Greve ◽  
Antônio Sérgio A.P. Terreri ◽  
...  
Keyword(s):  
Angular Velocity ◽  
Muscular Strength ◽  
Elderly Women ◽  
Previous History ◽  
Peak Torque ◽  
Contralateral Side ◽  
Lower Limbs ◽  
Isokinetic Dynamometer ◽  
Knee Flexor ◽  
Torque Values

OBJECTIVE: To assess knee flexor-extensor muscular strength in elderly women with no previous history of musculoskeletal disorders on the lower limbs using an isokinetic dynamometer, in order to obtain data that could be used as a comparative parameter in the evaluation of elderly women with knee disorders, thus facilitating a better rehabilitation of these patients. METHODS: Twenty-six volunteers aged 75 to 83 years were studied using a Cybex® 6000 isokinetic dynamometer. The chosen angular velocity was 60 º/s, and concentric exercise was used for either flexion or extension. The studied parameters were: peak torque, angle of peak torque, and flexor-extensor torque rate. RESULTS: There were no differences between dominant (D) and nondominant (ND) knee peak torque values. This was true for both flexor (D = 42.46 ± 9.09 Nm / ND = 40.65 ± 9.38 Nm) and extensor (D = 76.92 ± 13.97 Nm / ND = 77.65 ± 15.21 Nm) movements. The descriptive statistical analysis of the values obtained for the flexor-extensor peak torque rate and for the angle of occurrence of peak torque was the same for the dominant and nondominant sides. CONCLUSIONS: The values of peak torque for the contralateral side can be used as a reference during rehabilitation of elderly women with acute disease of the knee, and the angular velocity of 60 º/s is proper and safe for isokinetic assessment of elderly people.

Ultrasound Treatment Does Not Affect Postexercise Muscle Strength Recovery or Soreness

1999 ◽  
Vol 8 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Carrie Plaskett ◽  
Peter M. Tiidus ◽  
Lori Livingston
Keyword(s):  
Muscle Strength ◽  
Muscle Soreness ◽  
Peak Torque ◽  
Quadriceps Muscle ◽  
Knee Extension ◽  
Similar Treatment ◽  
Delayed Onset ◽  
Strength Recovery ◽  
Pulsed Mode ◽  
Torque Values

Ten volunteers (19-23 years old) performed 9 sets of 12 bilateral knee-extension exercises at 60% 1RM. Following exercise, 4 ultrasound treatments (5-cm transducer head, 1.0-MHz frequency, pulsed mode at 1.0 W/cm2) were applied for 8 min daily to the quadriceps muscle of a randomly selected treatment leg. The placebo leg received similar treatment with the ultrasound apparatus turned off. Knee-extension peak torque values and delayed onset muscle soreness (DOMS) were assessed on each leg prior to exercise and at 20 min and 24, 48, 72, and 96 hr postexercise. Postexercise peak torques declined to 60-70% of preexercise values and returned to normal by 96 hr. DOMS sensation peaked 24 hr postexercise and diminished thereafter. No significant differences in peak torque or DOMS were noted between ultrasound- or placebo-treated legs at any time postexercise. Hence ultrasound, as applied in this study, does not appear to be effective in enhancing postexercise muscle strength recovery or in diminishing DOMS.

Estimations of One Repetition Maximum and Isometric Peak Torque in Knee Extension Based on the Relationship Between Force and Velocity

2016 ◽  
Vol 30 (4) ◽  
pp. 980-988 ◽  
Author(s):  
Yoshito Sugiura ◽  
Yasuhiko Hatanaka ◽  
Tomoaki Arai ◽  
Hiroaki Sakurai ◽  
Yoshikiyo Kanada
Keyword(s):  
Peak Torque ◽  
Knee Extension ◽  
Repetition Maximum ◽  
The Relationship

scholarly journals Effects of Adding Inter-Set Static Stretching to Flywheel Resistance Training on Flexibility, Muscular Strength, and Regional Hypertrophy in Young Men

2021 ◽  
Vol 18 (7) ◽  
pp. 3770
Author(s):  
Masatoshi Nakamura ◽  
Hirotaka Ikezu ◽  
Shigeru Sato ◽  
Kaoru Yahata ◽  
Ryosuke Kiyono ◽  
...  
Keyword(s):  
Resistance Training ◽  
Lower Limb ◽  
Muscular Strength ◽  
Young Men ◽  
Muscle Thickness ◽  
Peak Torque ◽  
Knee Extension ◽  
Static Stretching ◽  
Joint Flexibility ◽  
Significant Difference

Performing static stretching (SS) during resistance training (RT) rest periods is posited to potentiate muscular adaptations, but the literature is scarce on the topic. Thus, the purpose of this study was to investigate the effects of adding inter-set SS to a lower-limb flywheel RT program on joint flexibility, muscular strength, and regional hypertrophy. Sixteen untrained male adults (21 ± 1 y) completed the study, where they performed progressive flywheel bilateral squatting twice a week for 5 weeks. One leg of each participant was randomly allocated to perform SS during the inter-set rest period (RT+SS), while the other leg served as control (RT only). Before and after the intervention, knee flexion range of motion; knee extension isometric, concentric, and eccentric peak torque; 1-repetition maximum; and muscle thickness of the lower-limb muscles were assessed. Following the training period, additional effects were observed for the inter-set SS side on increasing joint flexibility (p < 0.05), whereas the average increase in strength measures was 5.3% for the control side, and 10.1% for the inter-set SS side, however, SS intervention induced significantly greater gains only for knee extension isometric strength, but not for dynamic 1-RM, concentric, and eccentric tests. Hamstrings and gluteus maximus did not hypertrophy with training; increases quadriceps muscle thickness depended on the site/portion analyzed, but no significant difference was observed between legs (average: RT = 7.3%, RT+SS = 8.0%). The results indicate that adding inter-set SS to RT may provide large gains in flexibility, slightly benefits for muscular strength (especially for isometric action), but do not impact muscle hypertrophy in untrained young men.

A Comparison of Concentric Knee Extension Performance Using the Cybex 6000 Nonpowered and Powered Mode for Work and Peak Torque Values

1993 ◽  
Vol 3 (4) ◽  
pp. 216-221
Author(s):  
Lori Jean Brown ◽  
Sonja Leah Wiberg Parker ◽  
Julie M. Chandler ◽  
Terry R. Malone
Keyword(s):  
Peak Torque ◽  
Knee Extension ◽  
Torque Values

The Reliability of Four Different Methods of Calculating Quadriceps Peak Torque and Angle-Specific Torques at 30°, 60°, and 75°

1993 ◽  
Vol 2 (4) ◽  
pp. 243-250 ◽  
Author(s):  
Brent L. Arnold ◽  
Dawid H. Perrin
Keyword(s):  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Peak Torque ◽  
Knee Extension ◽  
Eccentric Contractions ◽  
Isokinetic Dynamometer ◽  
Intraclass Correlation Coefficients ◽  
Best Value

Twelve university females were studied to determine the reliability of four different methods of calculating concentric and eccentric peak torque (PT) and angle-specific torques (ASTs) for knee extension. Each subject was tested on the Kin-Corn isokinetic dynamometer on two separate occasions, performing five concentric and eccentric contractions at 60° • s−1. PT and AST at 30°, 60°, and 75° were calculated by averaging the first three contractions, averaging all five contractions, taking the single best value of the first three contractions, and taking the single best value of all five contractions. Intraclass correlation coefficients derived from these calculations showed high correlation among the four methods. Additionally, z tests performed on correlation coefficients transformed to Fisher's Z revealed no differences between pairs of correlation coefficients. These data appear to show there is no difference among the four methods of calculating PT and AST.

The Effect of Whey Protein Supplementation with and Without Creatine Monohydrate Combined with Resistance Training on Lean Tissue Mass and Muscle Strength

2001 ◽  
Vol 11 (3) ◽  
pp. 349-364 ◽  
Author(s):  
Darren G. Burke ◽  
Philip D. Chilibeck ◽  
K. Shawn Davison ◽  
Darren C. Candow ◽  
Jon Farthing ◽  
...  
Keyword(s):  
Resistance Training ◽  
Whey Protein ◽  
Bench Press ◽  
Peak Torque ◽  
Knee Extension ◽  
Protein Supplementation ◽  
Creatine Monohydrate ◽  
Lean Tissue ◽  
Tissue Mass ◽  
Lean Tissue Mass

Our purpose was to assess muscular adaptations during 6 weeks of resistance training in 36 males randomly assigned to supplementation with whey protein (W; 1.2 g/kg/day), whey protein and creatine monohydrate (WC; 0.1 g/kg/day), or placebo (P; 1.2 g/kg/day maltodextrin). Measures included lean tissue mass by dual energy x-ray absorptiometry, bench press and squat strength (1-repetition maximum), and knee extension/flexion peak torque. Lean tissue mass increased to a greater extent with training in WC compared to the other groups, and in the W compared to the P group (p < .05). Bench press strength increased to a greater extent for WC compared to W and P (p < .05). Knee extension peak torque increased with training for WC and W (p < .05), but not for P. All other measures increased to a similar extent across groups. Continued training without supplementation for an additional 6 weeks resulted in maintenance of strength and lean tissue mass in all groups. Males that supplemented with whey protein while resistance training demonstrated greater improvement in knee extension peak torque and lean tissue mass than males engaged in training alone. Males that supplemented with a combination of whey protein and creatine had greater increases in lean tissue mass and bench press than those who supplemented with only whey protein or placebo. However, not all strength measures were improved with supplementation, since subjects who supplemented with creatine and/or whey protein had similar increases in squat strength and knee flexion peak torque compared to subjects who received placebo.

scholarly journals Knee Muscles Isokinetic Evaluation after a Six-Month Regular Combined Swim and Dry-Land Strength Training Period in Adolescent Competitive Swimmers

2015 ◽  
Vol 49 (1) ◽  
pp. 195-200 ◽  
Author(s):  
Athanasios A. Dalamitros ◽  
Vasiliki Manou ◽  
Kosmas Christoulas ◽  
Spiros Kellis
Keyword(s):  
Strength Training ◽  
Knee Extensor ◽  
Peak Torque ◽  
Knee Extension ◽  
Training Period ◽  
Similar Data ◽  
Dry Land ◽  
Isokinetic Testing ◽  
Torque Values ◽  
Competitive Swimmers

Abstract Previous studies demonstrated significant increases in the shoulder internal rotators’ peak torque values and unilateral muscular imbalances of the shoulder rotators after a competitive swim period. However, there are no similar data concerning the knee muscles. The purpose of the current study was to examine the effects of a six-month training period on knee flexor and extensor peak torque values, examine a possible bilateral strength deficit and evaluate the unilateral strength balance in competitive swimmers. Eleven male adolescent swimmers (age: 14.82 ± 0.45 years) were tested for concentric knee extension and flexion peak torque (60°/s) with an isokinetic dynamometer, before and after a regular combined swim and dry-land strength training period. A trend towards greater improvements in the knee extensor compared to flexor muscles peak torque was observed. Furthermore, the bilateral strength deficit remained almost unchanged, whereas unilateral strength imbalance was increased for both limbs. However, all results were nonsignificant (p > 0.05). According to the data presented, a six-month regular combined swim and dry-land strength training period caused non-significant alterations for all the parameters evaluated during isokinetic testing. This study highlights the fact that competitive adolescent swimmers demonstrated unilateral knee strength imbalances throughout a long period of their yearly training macrocycle.

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