Changes in Muscle Morphology, Electromyographic Activity, and Force Production Characteristics During Progressive Strength Training in Young and Older Men

Häkkinen, Keijo; Newton, Robert U.; Gordon, Scott E.; McCormick, Matthew; Volek, Jeff S.; Nindl, Bradley C.; Gotshalk, Lincoln A.; Campbell, Wayne W.; Evans, William J.; Häkkinen, Arja; Humphries, Brendan; Kraemer, William J.

doi:10.1093/gerona/53a.6.b415

Cited by 339 publications

(322 citation statements)

References 52 publications

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“…Similar findings of a mismatch between the gains in ACSA and muscle fiber CSA after a period of resistance training has previously been found in both young (1) and old individuals (11,14,19). The observed increase in muscle fiber pennation angle (ϩ22%) in the present study indicates the importance of muscle architecture to explain for some of this mismatch, since a steeper muscle fiber pennation angle allows for a larger physiological fiber area for a given muscle volume and it should therefore be recognized that ACSA may not be a very representative measure of changes in the physiological CSA (1).…”

Section: Discussionsupporting

confidence: 85%

Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients

Suetta

Andersen²,

Dalgas³

et al. 2008

Journal of Applied Physiology

155

138

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Magnusson SP, Kjaer M. Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients. J Appl Physiol 105: 180 -186, 2008. First published April 17, 2008 doi:10.1152/japplphysiol.01354.2007.-Although the negative effects of bed rest on muscle strength and muscle mass are well established, it still remains a challenge to identify effective methods to restore physical capacity of elderly patients recovering from hospitalization. The present study compared different training regimes with respect to muscle strength, muscle fiber size, muscle architecture, and stair walking power in elderly postoperative patients. Thirty-six patients (60 -86 yr) scheduled for unilateral hip replacement surgery due to hip osteoarthritis were randomized to either 1) resistance training (RT: 3/wk ϫ 12 wk), 2) electrical stimulation (ES: 1 h/day ϫ 12 wk), or 3) standard rehabilitation (SR: 1 h/day ϫ 12 wk). All measurements were performed at baseline, at 5 wk and 12 wk postsurgery. After 12 wk of resistance training, maximal dynamic muscle strength increased by 30% at 60°/s (P Ͻ 0.05) and by 29% at 180°/s (P Ͻ 0.05); muscle fiber area increased for type I (ϩ17%, P Ͻ 0.05), type IIa (ϩ37%, P Ͻ 0.05), and type IIx muscle fibers (ϩ51%, P Ͻ 0.05); and muscle fiber pennation angle increased by 22% and muscle thickness increased by 15% (P Ͻ 0.05). Furthermore, stair walking power increased by 35% (P Ͻ 0.05) and was related to the increase in type II fiber area (r ϭ 0.729, P Ͻ 0.05). In contrast, there was no increase in any measurement outcomes with electrical stimulation and standard rehabilitation. The present study is the first to demonstrate the effectiveness of resistance training to induce beneficial qualitative changes in muscle fiber morphology and muscle architecture in elderly postoperative patients. In contrast, rehabilitation regimes based on functional exercises and neuromuscular electrical stimulation had no effect. The present data emphasize the importance of resistance training in future rehabilitation programs for elderly individuals.aging; muscle power; exercise SARCOPENIA HAS LONG BEEN RECOGNIZED as a major cause of loss in muscle strength with old age. In fact, aging and disuse are two of the main conditions leading to skeletal muscle atrophy in humans. In both conditions, the loss of muscle mass leads to a decrease in muscle force production, and recent evidence suggests that a significant additional contribution might come from changes in muscle architecture (38,39). However, only a few studies have examined changes in muscle architecture and muscle fiber morphology in response to aging and physical training, and although the results suggest that a significant plasticity exists, there is generally a lack of data as to what extent different conditioning stimuli may affect muscle architecture in elderly individuals recovering from hospitalization.The loss of muscle mass with aging accelerates from the sixth decade onword, partly owing to a de...

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Section: Discussionsupporting

confidence: 85%

Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients

Suetta

Andersen²,

Dalgas³

et al. 2008

Journal of Applied Physiology

155

138

View full text Add to dashboard Cite

show abstract

“…In addition, rising-from-chair motion in the intervention group of the present study improved both aspects of endurance and quickness, which is represented by the 86.0% improvement in maximum counts of continuous repetition and the 10.9% improvement in maximum count in 10 seconds. These results support the idea that regular exercise leads to improvement of both quickness and muscle strength in the elderly as mentioned by Fukunaga 14,15) , although quick motion which requires instantaneous force may cause injury since type I fiber (slow twitch fiber) is more greatly atrophied than type II fiber (fast twitch fiber) in the elderly in general [17][18][19] .…”

Section: Discussionsupporting

confidence: 84%

Effects of Exercise on the Improvement of the Physical Functions of the Elderly

Hara

Shimada

2007

J Phys Ther Sci

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Abstract. The purpose of this study is to clarify the effects of exercise on the improvement of the physical functions of the elderly. Ten males and thirty-four females, 44 in total, living in or visiting health care facilities and special nursing homes for the elderly who were able to either walk independently or with walking aids were randomly divided into a treatment intervention group (TIG) and a control group (CG). The average age of the TIG was 84.4 ± 5.6 years old, and that of the CG was 85.6 ± 4.8 years old respectively. The training exercises of the TIG were standing up from a chair grasping parallel bars and raising arms with pet bottles 2 or 3 times a week for 6 months. In the TIG, increased mean values of each estimation parameter were recognized: muscle strength of upper and lower limbs, grip strength, thigh circumference, standing up, the movement of raising arms, walking time and number of steps for 10 m, Functional Reach Test and Timed up & Go Test. Moreover, significant differences between the TIG and the CG were found in each evaluation item (p<0.05). This study suggests that the continuation of light-load exercise is effective and imperative for the elderly to keep and improve their physical functions.

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“…In previous reports quadriceps CSA obtained at 50 % femur length have ranged from 68 to 88 cm 2 (Narici et al 1989(Narici et al , 1996bRutherford & Jones, 1992;Kanehisa et al 1994). In terms of changes evoked by resistance training, moderate increases (5-12 %) in anatomical CSA have been observed following 10-15 weeks of resistance training (Narici et al 1989;Rutherford & Jones, 1992;Higbie et al 1996;Häkkinen et al 1998), whereas somewhat greater changes (13 %) were reported following more prolonged periods of training (26 weeks; Narici et al 1996b). In comparison, 14 weeks of resistance training resulted in a 10 % increase in anatomical CSA in the present study.…”

Section: Anatomical Muscle Csa and Volumementioning

confidence: 93%

A mechanism for increased contractile strength of human pennate muscle in response to strength training: changes in muscle architecture

Aagaard¹,

Andersen²,

Dyhre‐Poulsen³

et al. 2001

The Journal of Physiology

562

493

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In human pennate muscle, changes in anatomical cross‐sectional area (CSA) or volume caused by training or inactivity may not necessarily reflect the change in physiological CSA, and thereby in maximal contractile force, since a simultaneous change in muscle fibre pennation angle could also occur. Eleven male subjects undertook 14 weeks of heavy‐resistance strength training of the lower limb muscles. Before and after training anatomical CSA and volume of the human quadriceps femoris muscle were assessed by use of magnetic resonance imaging (MRI), muscle fibre pennation angle (θp) was measured in the vastus lateralis (VL) by use of ultrasonography, and muscle fibre CSA (CSAfibre) was obtained by needle biopsy sampling in VL. Anatomical muscle CSA and volume increased with training from 77.5 ± 3.0 to 85.0 ± 2.7 cm2 and 1676 ± 63 to 1841 ± 57 cm3, respectively (±s.e.m.). Furthermore, VL pennation angle increased from 8.0 ± 0.4 to 10.7 ± 0.6 deg and CSAfibre increased from 3754 ± 271 to 4238 ± 202 μm2. Isometric quadriceps strength increased from 282.6 ± 11.7 to 327.0 ± 12.4 N m. A positive relationship was observed between θp and quadriceps volume prior to training (r = 0.622). Multifactor regression analysis revealed a stronger relationship when θp and CSAfibre were combined (R= 0.728). Post‐training increases in CSAfibre were related to the increase in quadriceps volume (r = 0.749). Myosin heavy chain (MHC) isoform distribution (type I and II) remained unaltered with training. VL muscle fibre pennation angle was observed to increase in response to resistance training. This allowed single muscle fibre CSA and maximal contractile strength to increase more (+16 %) than anatomical muscle CSA and volume (+10 %). Collectively, the present data suggest that the morphology, architecture and contractile capacity of human pennate muscle are interrelated, in vivo. This interaction seems to include the specific adaptation responses evoked by intensive resistance training.

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Changes in Muscle Morphology, Electromyographic Activity, and Force Production Characteristics During Progressive Strength Training in Young and Older Men

Cited by 339 publications

References 52 publications

Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients

Resistance training induces qualitative changes in muscle morphology, muscle architecture, and muscle function in elderly postoperative patients

Effects of Exercise on the Improvement of the Physical Functions of the Elderly

A mechanism for increased contractile strength of human pennate muscle in response to strength training: changes in muscle architecture

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