Journal of Applied Physiology Email Content Delivery
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 91: 1971-1976, 2001;
8750-7587/01 $5.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (30)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Cullen, D. M.
Right arrow Articles by Akhter, M. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Cullen, D. M.
Right arrow Articles by Akhter, M. P.
Vol. 91, Issue 5, 1971-1976, November 2001

Bone-loading response varies with strain magnitude and cycle number

D. M. Cullen1, R. T. Smith2, and M. P. Akhter1

1 Osteoporosis Research Center, Creighton University, Omaha, Nebraska 68131; and 2 North Carolina Wesleyan College, Rocky Mount, North Carolina 27804

Mechanical loading stimulates bone formation and regulates bone size, shape, and strength. It is recognized that strain magnitude, strain rate, and frequency are variables that explain bone stimulation. Early loading studies have shown that a low number (36) of cycles/day (cyc) induced maximal bone formation when strains were high (2,000 µepsilon ) (Rubin CT and Lanyon LE. J Bone Joint Surg Am 66: 397-402, 1984). This study examines whether cycle number directly affects the bone response to loading and whether cycle number for activation of formation varies with load magnitude at low frequency. The adult rat tibiae were loaded in four-point bending at 25 (-800 µepsilon ) or 30 N (-1,000 µepsilon ) for 0, 40, 120, or 400 cyc at 2 Hz for 3 wk. Differences in periosteal and endocortical formation were examined by histomorphometry. Loading did not stimulate bone formation at 40 cyc. Compared with control tibiae, tibiae loaded at -800 µepsilon showed 2.8-fold greater periosteal bone formation rate at 400 cyc but no differences in endocortical formation. Tibiae loaded at -1,000 µepsilon and 120 or 400 cyc had 8- to 10-fold greater periosteal formation rate, 2- to 3-fold greater formation surface, and 1-fold greater endocortical formation surface than control. As applied load or strain magnitude decreased, the number of cyc required for activation of formation increased. We conclude that, at constant frequency, the number of cyc required to activate formation is dependent on strain and that, as number of cyc increases, the bone response increases.

tibia; adult rat; strain; histology; mechanical loading


This article has been cited by other articles:


Home page
 Br. J. Sports. Med.Home page
P Zhang, G M Malacinski, and H Yokota
Joint loading modality: its application to bone formation and fracture healing
Br. J. Sports Med., July 1, 2008; 42(7): 556 - 560.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
K. J. Carlson and S. Judex
Increased non-linear locomotion alters diaphyseal bone shape
J. Exp. Biol., September 1, 2007; 210(17): 3117 - 3125.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
S. Srinivasan, B. J. Ausk, S. L. Poliachik, S. E. Warner, T. S. Richardson, and T. S. Gross
Rest-inserted loading rapidly amplifies the response of bone to small increases in strain and load cycles
J Appl Physiol, May 1, 2007; 102(5): 1945 - 1952.
[Abstract] [Full Text] [PDF]

Home page
 Br. J. Sports. Med.Home page
R A Santos-Rocha, C S Oliveira, A P Veloso, M Espanha, and R Dyson
Osteogenic index of step exercise depending on choreographic movements, session duration, and stepping rate * COMMENTARY * COMMENTARY
Br. J. Sports Med., October 1, 2006; 40(10): 860 - 866.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
A. Zumwalt
The effect of endurance exercise on the morphology of muscle attachment sites
J. Exp. Biol., February 1, 2006; 209(3): 444 - 454.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online