lower extremities and the functional capacity in this population. We hypothesized that muscle power output of the quadriceps femoris would have stronger association with physical activity and functional capacity than maximum dynamic strength in older men with COPD. Methods Participants An observational
María Hernández, Fabrício Zambom-Ferraresi, Pilar Cebollero, Javier Hueto, José Antonio Cascante and María M. Antón
Nobuaki Tottori, Tadashi Suga, Yuto Miyake, Ryo Tsuchikane, Mitsuo Otsuka, Akinori Nagano, Satoshi Fujita and Tadao Isaka
, previous studies have shown that a larger quadriceps femoris (QF) may be related to higher sprint performance because of a strong correlation between maximal knee extensor torque and sprint performance ( 4 , 10 , 13 , 21 ). Furthermore, Sugisaki et al ( 34 ) reported that a larger CSA of the adductors (ADD
Anna Lina Rahlf, Klaus-Michael Braumann and Astrid Zech
third of the quadriceps femoris muscle. The medial and lateral straps were applied in 45° knee flexion along the collateral medial and lateral ligaments. Patients in the sham group received a tape distal to the knee without tension and without affecting the knee joint (Figure 2B ). The tape was applied
Tarik Ozmen, Mert Aydogmus, Hanife Dogan, Derya Acar, Tuba Zoroglu and Mark Willems
Kinesio taping (KT) is a taping technique extensively used in rehabilitation of sports injuries; however, the effect of KT on delayed-onset muscle soreness is not entirely clear.
To investigate the effect of kinesio tape on the quadriceps femoris on muscle pain, flexibility, and sprint performance after squat exercise.
University research laboratory.
19 female university students (age 21.0 ± 1.2 y, weight 53.0 ± 4.6 kg, height 164 ± 4 cm).
Main Outcome Measures:
Pressure-pain threshold for quadriceps femoris was recorded using pressure algometry. Quadriceps femoris flexibility was measured as the range of motion of knee flexion with a stainless steel goniometer. Sprint-speed measurements were conducted using photocells placed at 0 and 20 m. All participants completed both conditions (KT application and no KT application) after a 1-wk washout period. Measurements were taken at baseline and 48 h postexercise. For the KT condition, KT was applied immediately before the exercise protocol and remained on the skin for 48 h.
Squat exercise reduced flexibility and increased pain and sprint time compared with baseline. KT application resulted in similar sprint time and muscle pain as the no-KT condition but maintained flexibility compared with baseline.
KT application immediately before squat exercise has no effect on muscle pain and short sprint performance but maintains muscle flexibility at 2 days of recovery.
Kenneth Meijer, Peter Bosch, Maarten F. Bobbert, Arthur J. van Soest and Peter A. Huijing
The influence of parameter values (i.e., fiber optimum lengths and moment arms) and simplification of the geometry of a Hill-type muscle model on the prediction of normalized maximal isometric knee extension moment to knee joint angle relationship was studied. For that purpose, the geometry of m. quadriceps femoris was modeled in considerable detail, and all parameter values were determined on one set of cadaver specimens that had been selected for muscular appearance. The predicted relationship was compared to that measured in human subjects over the full range of physiological knee angles, and a good correspondence was found (r = .96). The good correspondence could be attributed to the substitution of realistic parameter values into the model. Incorporating complex muscle geometry into the model resulted in a small additional improvement of the prediction. It was speculated that the variation in results of cadaver measurements among studies reflects true differences caused by individuals' levels of physical activity in the period preceding death.
Janne Sallinen, Arto Pakarinen, Mikael Fogelholm, Elina Sillanpää, Markku Alen, Jeff S. Volek, William J. Kraemer and Keijo Häkkinen
This study examined the effects of strength training and diet on serum basal hormone concentrations and muscle mass in aging women. Fifty-one women age 49 to 74 y were divided into two groups: strength training and nutritional counseling (n = 25), and strength training (n = 26). Both groups performed strength training twice a week for 21 wk. Nutritional counseling was given to attain sufficient energy and protein intake and recommended intake of fat and fiber. We found that the cross-sectional area of the quadriceps femoris increased by 9.5 ± 4.1% in the nutritional counseling group versus 6.8 ± 3.5% in the strength training only group after training (P < 0.052). Nutritional counseling evoked dietary changes such as increases in the proportion of energy from protein and the ratio of poly-unsaturated and saturated fatty acids. Strength training increased testosterone and testosterone/sex hormone-binding globulin ratio after the first half of training, but these returned to baseline values at the end of the entire training period. Changes in serum basal hormone concentrations did not differ between the groups. Our results support the conclusion that nutritional counseling can contribute to the increase in the muscle cross-sectional area during prolonged strength training in aging women.
Keitaro Kubo, Teruaki Komuro, Noriko Ishiguro, Naoya Tsunoda, Yoshiaki Sato, Naokata Ishii, Hiroaki Kanehisa and and Tetsuo Fukunaga
The present study aimed to investigate the effects of low-load resistance training with vascular occlusion on the specific tension and tendon properties by comparing with those of high-load training. Nine participants completed 12 weeks (3 days/week) of a unilateral isotonic training program on knee extensors. One leg was trained using low load (20% of 1 RM) with vascular occlusion (LLO) and other leg using high load (80% of 1 RM) without vascular occlusion (HL). Before and after training, maximal isometric knee extension torque (MVC) and muscle volume were measured. Specific tension of vastus lateralis muscle (VL) was calculated from MVC, muscle volume, and muscle architecture measurements. Stiffness of tendon-aponeurosis complex in VL was measured using ultrasonography during isometric knee extension. Both protocols significantly increased MVC and muscle volume of quadriceps femoris muscle. Specific tension of VL increased significantly 5.5% for HL, but not for LLO. The LLO protocol did not alter the stiffness of tendon-aponeurosis complex in knee extensors, while the HL protocol increased it significantly. The present study demonstrated that the specific tension and tendon properties were found to remain following low-load resistance training with vascular occlusion, whereas they increased significantly after high-load training.
Yanita McLeay, Stephen R Stannard, Toby Mundel, Andrew Foskett and Matthew Barnes
This study was designed to investigate the effects of alcohol consumption on recovery of muscle force when consumed immediately postexercise in young females. Eight young women completed 300 maximal eccentric actions of the quadriceps femoris muscle on an isokinetic dynamometer on two occasions in a randomized, cross-over design after which an alcoholic beverage (0.88g ethanol/kg body weight) or an iso-caloric placebo was consumed. Maximal isokinetic (concentric and eccentric) torque and isometric tension produced across the knee were measured in both the exercised and control leg predamage, 36 hr post, and 60 hr post damage. Venous blood creatine kinase (CK) activity and muscle soreness ratings were taken before damage and once per day to 60 hr post damage. Significant differences were observed between the exercised and control leg for maximal concentric, and eccentric torque and isometric tension (p < .05). A near significant Treatment × Time interaction was observed for isometric tension (p = .077), but not for concentric or eccentric torque. No main effects of treatment (alcohol) or interactions with Time × Leg or Leg × Treatment were observed. Perceived muscle soreness during box stepping and squatting showed significant time effects (p < .05), and CK activity did not significantly change. Our results indicate that the consumption of 0.88g ethanol/kg body weight following eccentric exercise-induced muscle damage does not affect recovery in the days following damage in females.
Matheus Barbalho, Victor Silveira Coswig, James Steele, James P. Fisher, Jurgen Giessing and Paulo Gentil
To compare the effects of different resistance training volumes on muscle performance and hypertrophy in trained men.
37 volunteers performed resistance training for 24 weeks, divided into groups that performed five (G5), 10 (G10), 15 (G15) and 20 (G20) sets per muscle group per week. Ten repetition maximum (10RM) tests were performed for the bench press, lat pull down, 45º leg press, and stiff legged deadlift. Muscle thickness (MT) was measured using ultrasound at biceps brachii, triceps brachii, pectoralis major, quadriceps femoris and gluteus maximus. All measurements were performed at the beginning (pre) and after 12 (mid) and 24 weeks (post)
All groups showed significant increases in all 10RM tests and MT measures after 12 and 24 weeks when compared to pre (p <0.05). There were no significant differences in any 10RM test or changes between G5 and G10 after 12 and 24 weeks. G5 and G10 showed significantly greater increases for 10RM than G15 and G20 for most exercises at 12 and 24 weeks. There were no group by time interaction for any MT measure
The results bring evidence of an inverted “U shaped” curve for the dose response curve for muscle strength. Whilst the same trend was noted for muscle hypertrophy, the results did not reach significance. Five to 10 sets per week might be sufficient for bringing about optimal gains in muscle size and strength in trained men over a 24-week period.
Matthew David Cook, Stephen David Myers, John Stephen Michael Kelly and Mark Elisabeth Theodorus Willems
Impaired glucose tolerance was shown to be present 48 hr following muscle-damaging eccentric exercise. We examined the acute effect of concentric and muscle-damaging eccentric exercise, matched for intensity, on the responses to a 2-hr 75-g oral glucose tolerance test (OGTT). Ten men (27 ± 9 years, 178 ± 7 cm, 75 ± 11 kg, VO2max: 52.3 ± 7.3 ml·kg-1·min-1) underwent three OGTTs after an overnight 12 hr fast: rest (control), 40-min (5 × 8-min with 2-min interbout rest) of concentric (level running, 0%, CON) or eccentric exercise (downhill running, –12%, ECC). Running intensity was matched at 60% of maximal metabolic equivalent. Maximal isometric force of m. quadriceps femoris of both legs was measured before and after the running protocols. Downhill running speed was higher (level: 9.7 ± 2.1, downhill: 13.8 ± 3.2 km·hr-1, p < .01). Running protocols had similar VO2max (p = .59), heart rates (p = .20) and respiratory exchange ratio values (p = .74) indicating matched intensity and metabolic demands. Downhill running resulted in higher isometric force deficits (level: 3.0 ± 6.7, downhill: 17.1 ± 7.3%, p < .01). During OGTTs, area-under-the-curve for plasma glucose (control: 724 ± 97, CON: 710 ± 77, ECC: 726 ± 72 mmol·L-1·120 min, p = .86) and insulin (control: 24995 ± 11229, CON: 23319 ± 10417, ECC: 21842 ± 10171 pmol·L-1·120 min, p = .48), peak glucose (control: 8.1 ± 1.3, CON: 7.7 ± 1.2, ECC: 7.7 ± 1.1 mmol·L-1, p = .63) and peak insulin levels (control: 361 ± 188, CON: 322 ± 179, ECC: 299 ± 152 pmol·L-1, p = .30) were similar. It was concluded that glucose tolerance and the insulin response to an OGTT were not changed immediately by muscle-damaging eccentric exercise.