Medicina Sportiva 2004 vol. 8 nr. 3-4

Adenylate kinase and 5’-AMP-activated protein kinase contribution to the regulation of skeletal muscle energetics
Grażyna Lutosławska, Marzena Niedbalska
Department of Biochemistry, Academy of Physical Education, Warsaw, Poland

Abstract
It is well documented that adenine nucleotides (ATP, ADP and 5’-AMP) are the primary high-energy phosphate-carrying species in all living cells. There is a wealth of studies concerning the ADP role in the regulation of muscle energetic processes. The 5’-AMP contribution to the regulation of muscle metabolism was mostly discussed in the context of glycogen phosphorylase activity and glycogen breakdown as well as purine nucleotide cycle role in energy metabolism in contracting muscle. Numerous studies during last decade have indicated that 5’-AMP-producing adenylate kinase reaction and 5’-AMP per se play a fundamental role in the regulation of cellular metabolism under stress conditions in the living systems mostly due to 5’-AMP contribution to the activation of protein kinase named 5’-AMP-activated protein kinase (AMPK). At present AMPK structure, properties and regulatory mechanism are well recognized and confirm its key role as a metabolic signal activating catabolic processes in the face of increased energy demands (for example under fasting condition, during ischemia or contraction). In contracting skeletal muscle AMPK activity is elevated causing phosphorylation (i.e. inactivation) of a key enzyme of de novo free fatty acid (FFA) synthesis – acetylCoA-carboxylase. In consequence malonyl-CoA concentration - a potent inhibitor of FFA entry into mitochondria and its oxidation decreases promoting fat utilization but decreasing carbohydrate contribution to energy-providing processes. Additionally, in the muscle AMPK at least partially contributes to the regulation of exercise-induced glucose uptake and glycogen synthesis. There is a few studies indicating that persistent muscle AMPK activation in endurance-trained muscle induces mitochondrial biogenesis and increases the activity of mitochondrial enzymes, thus may be responsible for greater contribution of aerobic metabolism to overall energy production in trained muscle. Additionally, elevated AMPK activity affects the expression of genes encoding uncoupling protein-3 (UCP-3) and peroxisome-proliferator-activated γ coactivator -1 (PGC-1) – both contributing to fat metabolism in the muscle.
Key words: muscle, energetic demands, adenylate kinase, 5’-AMP-activated protein kinase
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USA NATIONAL STRATEGY FOR INCREASING PHYSICAL ACTIVITY AMONG ADULTS AGE 50 AND OLDER
Wojtek Chodzko-Zajko¹, Lisa Sheppard¹, Jane Senior², Chae hee Park¹,
Terry Bazzarre³, Robin Mockenhaupt^3
1 Department of Kinesiology, University of Illinois at Urbana-Champaign, USA
² American College of Sports, Medicine Indianapolis, Indiana, USA
³ Robert Wood Johnson Foundation, Princeton, New Jersey, USA

Abstract
On May 1, 2001, a coalition of national organizations released a major planning document designed to develop a national strategy for the promotion of physically active lifestyles among the mid-life and older adult population. The National Blueprint: Increasing Physical Activity Among Adults Age 50 and Older was developed with input from 46 organizations with expertise in health, medicine, social and behavioral sciences, epidemiology, gerontology/geriatrics, clinical science, public policy, marketing, medical systems, community organization, and environmental issues. The Blueprint notes that, despite a wealth of evidence about the benefits of physical activity for mid-life and older persons, there has been little success in convincing age 50+ Americans to adopt physically active lifestyles. The Blueprint identifies barriers in the areas of research, home and community programs, medical systems, public policy and advocacy, and marketing and communications. In addition to identifying barriers, the Blueprint proposes a number of concrete strategies that could be employed in order to overcome the barriers to physical activity in society at large.
Objective: This report summarizes the outcome of the National Blueprint Consensus Conference that was held in October 2002. In this conference, representatives of more than 50 national organizations convened in Washington, D.C. with the goal of identifying high priority and high feasibility strategies which would advance the National Blueprint and which could be initiated within the next 12 to 24 months.
Results: Participants in the consensus conference were assigned to one of five breakout groups: home and community, marketing, medical systems, public policy, and research. Each breakout group was charged with identifying the three highest priority strategies within their area for effectively increasing physical activity levels in the mid-life and older adult population. In addition to the 15 strategies identified by the breakout groups, three “cross-cutting” strategies were added which were considered to be broad-based in scope and which applied to more than one of the breakout themes. A national organization was identified to take the lead in planning and implementing each strategy. A summary of the 18 strategies and lead organizations is presented.
Conclusions: The National Blueprint Consensus Conference has identified an ambitious agenda of strategies and tactics that will need to be implemented in order to overcome societal barriers to physical activity among the mid-life and older adult population. More than 50 national organizations have expressed a commitment to work towards the implementation of the Blueprint agenda. Eighteen priority strategies have been identified in the areas of home and community, marketing, medical systems, public policy, and research. The organizations charged with the task of implementing the high priority strategies will use professional networks and established delivery channels and communication systems to translate this plan into action.
Key words: physical activity, public health, public policy, aging, quality of life, chronic disease
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EVALUATION OF TREATMENT EFFICACY OF UPPER EXTREMITY EFFORT DEEP VENOUS THROMBOSIS IN ATHLETES
Robert Juszkat, Fryderyk Pukacki, Maciej Zieliński, Grzegorz Oszkinis
Department of Clinical Radiology in the Radiology Institute, University of Medical Sciences, Poznan,
Department of General and Vascular Surgery, University of Medical Sciences, Poznan,

Abstract
Purpose: The purpose of the study was to evaluate the treatment results of upper extremity effort Deep Venous Thrombosis (DVT) and coexistent Thoracic Outlet Syndrome (TOS) in athletes.
Materials and Methods: The study included 13 physically active patients from 19 to 38 years of age with upper extremity deep venous thrombosis. The diagnosis of DVT was based on clinical examination and radiological imaging evaluation with phlebography. Fibrinolytic treatment was based on administration of streptokinase through a catheter placed in the vein in contact with the thrombus. Streptokinase infusion was continued for 2 to 3 days and subsequently replaced with intravenous administration of heparin and oral anticoagulants. After 6 to 8 weeks following fibrinolytic treatment, all patients with signs of subclavian vein compression underwent a decompressing operative procedure such as resection of the first rib or accessory cervical rib.
Results: Successful recanalization of thrombosed veins was achieved in 10 patients at 48 to 72 hours after streptokinase infusion. In remaining 3 patients, only partial patency was restored. 11 patients underwent first thoracic rib resection, and the remaining 2 patients had their accessory cervical rib resected. All operated patients returned to their normal physical state, and to this date no signs of blood retention in the periphery have been observed.
Conclusions: These findings confirm that TOS-related DVT of upper extremities should be treated with immediate thrombolysis combined with delayed surgical decompression, especially in cases of confirmed compression of the subclavian vein.
Key words: effort thrombosis, phlebography, thrombolytic therapy, Paget-Schroetter syndrome
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INTERNATIONAL Symposium
Medicina sportiva 2004

ABSTRACTS

KEYNOTE SPEAKERS’ LECTURES

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POSTER PRESENTATIONS