CARDIAC REHABILITATION
Measuring the functional capacity requirements of farmers to devise most effective cardiac rehabilitation program
Farmers come from sturdy stock. Physically active, they must be healthy to work their land and keep up with the daily demands of farming. Farmers also experience heart disease. Classified as industrial athletes by the American College of Sports Medicine( ACSM), they are now subject to updated cardiac rehabilitation and return-to-work guidelines from the ACSM. These guidelines include specificity of training encompassing muscle groups, movements, and energy systems that these patients use during occupational tasks. However, many cardiac rehab programs still rely on traditional protocol that consists primarily of aerobic exercise.
Jenny Adams, PhD, was a primary researcher in a study conducted to measure the metabolic cost of typical farming tasks and to compare two methods of calculating training intensities. Adams collaborated with several other researchers and the Kansas State Agronomy Department on the study.
Adams says the goal of the study was to design more effective cardiac rehab training that supports industrial athletes to return to work safely and confidently after experiencing a cardiac event. The aims of the study were to:
• Measure the MET level required for typical farming tasks and compare it with the 8-MET goal commonly used in traditional cardiac rehab programs
To develop the study tasks, the research team interviewed several farmers about the work they regularly do. Four task-specific stations were set up:
• Loading hay bales – 10 square bales each weighing 29 to 32 kg
• Digging fence postholes – using a clamshell-style posthole digger for three minutes or to 61 cm
• Filling seed poppers – equivalent of eight seed hoppers were each filled with 45.3 kg of grain
• Shoveling grain – a pile of grain was shoveled from the floor into a wheelbarrow
Heart rate and blood pressure were measured before and after completion of the farming tasks. Participants were fitted with a heart rate monitor chest strap and a K4 b2 metabolic system that measured carbon dioxide production, oxygen uptake, and heart rate data during testing.
To determine the training intensity that would have been calculated by the ACSM-recommended HRR method, researchers applied each participant’ s data from each task to a predetermined equation and solved for the intensity variable.
Complete data was collected and recorded for 28 participants. During the farming tasks, the participants reached mean heart rates that were significantly higher than their RHR + 30, suggesting that using the latter as a training target heart rate would be inadequate for preparing a farmer
MEASURING INNOVATION IN HEART AND VASCULAR CARE
“ Traditional cardiac rehab may be appropriate for patients who are primarily non active or have jobs that aren’ t physically demanding. However, industrial athletes, including farmers, require a higher mode and intensity of cardiac rehab.”
Jenny Adams, PhD
Senior research associate, Baylor Hamilton Heart and Vascular Hospital
• Compare two methods of calculating training intensities( RHR + 30 vs 40 %-80 % of HRR) to determine whether either yields appropriate levels for farmers who want to return to work after a cardiac event.
Thirty-one healthy participants, men and women aged 20 to 64 years, were recruited for the study. The study was conducted at the Kansas State University Agronomy Farm in Manhattan, KS. Baylor Research Institute’ s Institutional Review Board approved the study. return to work after a cardiac event. The participants performed the tasks at 60 to 70 percent of HRR, which is within the ACSM’ s current recommendation of using 40 to 80 percent of HRR as a goal for exercise training intensity in cardiac rehabilitation. On the basis of the results from this study and prior studies, the researchers advocate a combined approach of aerobic exercise and supervised resistance training, using task-specific exercises, for the cardiac rehabilitation of farmers who want to return to work.
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