CROSS SYSTEM RELIABILITY OF COSMED K4b2 vs. PARVO 2400 TRUE ONE METABOLIC SYSTEMS

CROSS SYSTEM RELIABILITY OF COSMED K4b2 vs. PARVO 2400 TRUE ONE METABOLIC SYSTEMS K.R. Cochrane, S.E. Gaskill, FACSM University of Montana, Missoula, MT During the development of a new fitness test for Wildland Firefighting, we needed to compare laboratory VO2 testing using a Parvo medics 2400 True One metabolic cart with field data collected with a Cosmed K4b2 system. The field test VO2 data were consistently slightly higher than the lab data at identical work rates during 20 kg load carriage. PURPOSE: To examine the validity of the Cosmed with the Parvo metabolic system and the ASCM equations. METHODS: Thirty subjects (17 male; 13 female) participated in the study. Upon arrival to the lab, subjects were outfitted with a 20kg. backpack and performed a five-minute warm up at a self-selected intensity. Subjects then completed two identical five-minute steady state stages while wearing the backpack. Each stage was randomly selected for monitoring order with the Cosmed and Parvo system. Subjects walked on a treadmill at an assigned speed between 2-3.5 MPH (mean=3.1 ± 0.4 MPH) and grade between 3-9% (mean=6.0 ± 2.5%). VO2, Ve and O2 extraction data using the Cosmed or Parvo metabolic systems and estimated VO2 (ACSM prediction equations) were analyzed using a one-way repeated measures ANOVA or dependent t-tests (for comparisons of Ve and O2 extraction). Significance was established at p\u3c0.05. RESULTS: The Cosmed measured a higher VO2 compared to the Parvo and ACSM equations (27.5 ± 5.7, 25.4 ± 5.6, and 25.5 ± 5.5 ml•kg-1•min-1, respectively, p\u3c0.05). The Ve for Cosmed was higher compared to the Parvo (44.4 ± 14.3 vs. 40.6 ± 13.4 L•min-1, respectively, p\u3c0.05). There was no difference between the Cosmed or Parvo for percent expired 02. CONCLUSION: Although the Cosmed VO2 and Ve values were slightly higher than the Parvo values, the differences were small and within a reasonable range for energy expenditure estimation in a field vs. laboratory setting. We are currently validating Ve in the two systems

HEALTH STATUS IMPROVEMENTS IN AT-RISK CVD SUBJECTS FOLLOWING A STUDENT INTERVENTION

HEALTH STATUS IMPROVEMENTS IN AT-RISK CVD SUBJECTS FOLLOWING A STUDENT INTERVENTION E.N. Simpson, S.E. Gaskill, FASCM. The University of Montana, Missoula, MT Lifestyle behavior changes are often effective methods to reduce the risk of cardiovascular disease (CVD). The Health and Human Performance Department at the University of Montana offers a free stress testing program with behavior change counseling by undergraduate students as part of a service learning class. PURPOSE: The purpose of this study was to evaluate changes in community members following a cardiovascular stress test and behavior-change intervention led by undergraduate students in the Exercise, Disease, and Aging class at the University of Montana. METHODS: Over the course of 20 semesters (fall 2003- spring 2013), 715 subjects (age 58 3.8 years) from the Missoula community participated in stress testing. Prior to testing, subjects filled out a Par-q, quality of life questionnaire, and consented to the testing. Subjects were administered a Bruce protocol treadmill test with full ECG to 85% HRmax or symptom limited endpoints. Body composition, blood lipids and cholesterol, blood glucose, flexibility and strength measurements were also made. Students then worked with clients to change lifestyle behaviors to reduce risk factors for CVD. RESULTS: Three year follow-up data showed clients lost significant weight (-21.7±2.2 lbs), improved quality of life (60±4.8%), and increased physical activity from 48.7 to 145.9 minutes per week. Additionally, lipid profiles improved, lowering total cholesterol from 250.5±6.0mg/dL to 201.1±6.6mg/dL, pre and post, respectively. CONCLUSIONS: These data show that the service learning class can effectively aid community members in implementing lifestyle changes that may have significant, positive effects on cardiovascular and overall health

CREATING A HIGHER MINIMUM FITNESS LEVEL FOR WILD LAND FIREFIGHTERS

CREATING A HIGHER MINIMUM FITNESS LEVEL FOR WILD LAND FIREFIGHTERS N. J. Hallfrisch, J.M. Stafford, J.C. Cabrera, S.E. Gaskill FACSM University of Montana, HHP Dept. Missoula, MT Currently the 45 pound pack test for wild land firefighters which requires a VO2 of 21.5 ml*kg-1*min-1 does not accurately reflect the aerobic capacity of 28-35 ml*kg-1*min-1 required for wild land firefighting (WLFF). PURPOSE: Our aim was to create a new test (3 miles, uphill with a 55 pound pack) more closely matching the aerobic and strength capacity necessary for wild land firefighting. METHODS: We tested 23 males and 11 females across 357 5 minute stages of varied speed (2.2-4.1 mph) and grade (2-14%). Subjects were of moderate to high fitness, age =23.09 ± 3.26 years, weight =75.44 ± 11.22 kg and height =175.06 ± 8.51 cm. The subjects were required to carry a 55 pound pack during all stages. The subject’s VO2 and heart rate were measured during the entire trial and averaged for the last two minutes of each stage. Multiple regression analysis was used to calculate prediction equations for VO2 (ml*kg-1*min-1). RESULTS: A new regression equation for the energy cost of carrying a 22 kg pack was calculated [VO2 (ml*kg-1*min-1) = 911.84 x mph) + (188 x % grade) -19.87, R=0.85, p\u3c0.001] which averaged 2.1 ml O2*kg-1*min-1 above that predicted by the ACSM equations. This test requires VO2 values reflective of actual aerobic capacity of 28-35 ml*kg-1*min-1 needed during WLFF. CONCLUSION: Data from this new test can be used to develop time standards for a 3 mile hike carrying 22kg (55 pounds) up a known grade in the range of 2-14%

Effect of an 8-weeks aerobic training program in elderly on oxidative stress and HSP72 expression in leukocytes during antioxidant supplementation.

OBJECTIVE: To investigate the effect of aerobic training in the context of antioxidant supplementation on systemic oxidative stress and leukocytes heat shock protein (Hsp)72 expression in the elderly. DESIGN: Sixteen septuagenarians (8 males and 8 females, mean age 74.6) were supplemented with Vitamin C and E (respectively 500 and 100mg per day) and randomly assigned either to sedentary (AS) or individualized aerobically trained (AT) group for 8 weeks. METHODS: Plasma Vitamin C and E concentrations and aerobic fitness, as well as resting and post graded exercise (GXT) Hsp72 expression in leukocytes, plasma levels of thiobarbituric acid reactive substances (TBARS) and advanced oxidation protein product (AOPP) were measured pre and post training / supplementation. RESULTS: At the end of the intervention, the two groups showed a significant increase in resting plasma vitamin C and E (approximately 50 and 20% increase respectively) and a significant decrease in both resting and post GXT plasma TBARS and AOPP (approximately 25 and 20% decrease respectively). These changes were of similar magnitude in the two groups. The reduced oxidative stress was concomitant with a 15% decreased expression of Hsp72 in monocytes and granulocytes in both groups. CONCLUSION: This study provides evidence that in elderly, increased concentration of antioxidant vitamins C and E is associated with a reduction in oxidative stress and leukocytes Hsp72. In this context, 8 weeks of aerobic training has no impact on oxidative stress or leukocytes Hsp72 expression in elderly people

Breast cancer hypothesis: a single cause for the majority of cases

STUDY OBJECTIVE—The main cause of breast cancer remains unknown. Numerous causal factors or predisposing conditions have been proposed, but account for only a small percentage of the total disease. The current search for multiple causes is unavailing. This report explores whether any single aetiological agent may be responsible for the majority of cases, and attempts to define its properties.
METHODS—Examination of all relevant epidemiological and biological evidence.
MAIN RESULTS—Genetic inheritance is not the main cause of breast cancer because most cases are sporadic, there is a low prevalence of family history, and genetically similar women have differing rates after migration. Environmental exposure, such as pollution by industrialisation, is not a major cause, as deduced from a spectrum of epidemiological data. The possibility of infection as cause is not persuasive as there is no direct biological evidence and no epidemiological support. Oestrogen status is closely related to breast cancer risk, but there are numerous inconsistencies and paradoxes. It is suggested that oestrogens are not the proximate agent but are promoters acting in concert with the causal agent. Dietary factors, and especially fat, are associated with the aetiology of breast cancer as shown by intervention and ecological correlation studies, but the evidence from case-control and cohort studies is inconsistent and contradictory.
CONCLUSIONS—The hypothesis that best fits the epidemiological data is that dietary fat is not itself the causal agent, but produces depletion of an essential factor that is normally protective against the development of breast cancer. Many of the observed inconsistencies in the epidemiology are explainable if deficiency of this agent is permissive for breast cancer to develop. Some properties of the putative agent are outlined, and research investigations proposed.


Keywords: breast cance