The effect of an isotonic weight-training program upon bone density and selected indices of bone turnover in early postmenopausal women /
Year: 1989
Type: article
Abstract: a 9-month isotonic weight-training program.2..There will be no pre-to post-training differences in serun osteocalcin, serun alkaline phosphatase, or urinary hydroxyproline/creatinine after participation in a 9-month isotonic weighttraining program.3.There will be no post-training differences in bone density at the radius/ulna, lunbar vertebrae, and femur between the weight-training and control groups.4.There will be no post-training differences in serum osteocalcin, serun alkaline phosphatase, or urinary hydroxyproline/creatinine between the weight-training and control groups.5.There will be no pre-post-training differences in systemic factors which could influence bone metabolism (parathyroid hormone, thyroxine, free thyroxine index, vitamin D, cortisol, and dehydroepiandrosterone sulphate).Definition of Terms For the purposes of this investigation, the following definitions were used: Alkaline Phosphatase -An enzyme generally thought to play an important role in the bone mineralization process and reflects activity of the cells responsible for bone formation.It is frequently used as a biochemical marker of bone turnover.Bone Mineral Content (BMC) -The quotient of mineral content and bone width determined b y single-photon absorptiometry.Bone Mineral Density (BMP) -Bone mass per unit projected scan area as determined by dual-photon absorptiometry.Bone Turnover -The cyclic process that occurs in bone involving bone breakdown and formation which is important in the maintenance and repair of bone tissue.For the purpose of this investigation, bone turnover may be considered synonymous with bone remodelling.Bone Resorption -The activity of bone breakdown which is a part of the bone remodelling process.Osteoclasts, a type of bone cell, are responsible for the resorption process.The hormones which facilitate bone resorption are parathyroid hormone and calcitriol (1,25 dihydroxyvitamin D).Cortical Bone -A type of hard, dense bone that is a primary component of the outer shell of all bones.Cortical bone comprises 80% of total bone volune, but only about onethird of the total bone surface.It has a relatively low metabolic activity level.Creatinine -An organic compound derived from creatine.The clearance of creatinine is used as an indicator of glomerular filtration rate.Dual-Photon Absorptiometry (DPA) -A non-invasive technique used to measure bone density in the lumbar spine and femur.Hydroxyproline -This imino acid is found primarily in collagen.O n a collagen-free diet, urinary hydroxyprol ine is used to assess collagen metabolism, specifically, the breakdown of bone.Isotonic Contraction -muscular action where the muscle shortens as work is being done against a constant load.Maximum Strength -The greatest amount of weight that can be lifted by a muscle group only once, for a specific exercise.Osteocalcin -A protein found only in bone tissue and believed to be produced by the osteoblast (bone forming cell).It is used as a
Author: Leslie A. Pruitt
Institution: The Ohio State University
Language: English
Subfield: Orthopedics and Sports Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W621094388