In 1990, I worked as a weekend guide for Pocono Whitewater Rafting on the Lehigh River in Pennsylvania. One day, after running a modest section of the river, a middle-aged client was knocked out of the raft. We pulled him back in, and he soon began complaining of difficulty breathing and mid-back and chest pain.
Our experienced lead guide, also an EMT, took all necessary precautions in treating the patient and determined the injury wasn't cardiovascular. EMTs from nearby Hazelton responded and decided to dispatch a MedEvac helicopter, just in case it was a cardiovascular emergency. Nonetheless, the big question was, "How are the ambulance and helicopter going to get to us?" The only way either was going to gain access to this patient was by getting him to the other side of the river and up a steep ravine.
Although our fully immobilized victim was hefty, we easily ferried the raft across the river. But as we began our ascent up the ravine, we realized we were going to earn our wages for the dayƒfour of us had a hold of each corner of the backboard and, with the aid of a couple ropes anchored to a forest service vehicle at the top of the ravine, we were able to pull the patient up. Many grunts, groans and heartbeats later, we reached the road at the upper ravine, where the patient was loaded into the MedEvac helicopter.
Exhausted, we just looked at each other and shook our heads as we sat trying to catch our breath for the next 15 minutes. It was clear the job would've been easier if we had been in better shape.
The Core of Fitness
You've likely considered a physical fitness improvement program following a call like the one above, because a call that drains us physically will also interfere with our ability to provide effective care. This new column will focus on the various components of physical fitness, guide you in practical self-assessments and help you develop a program that will improve your fitness while working around your schedule.
So, what is physical fitness? The definition I tend to use, which also pertains to the EMT in a physically demanding situation, is old but worth including: "Physical fitness is the ability to last, to bear up, to withstand stress, and to persevere under difficult circumstances where an unfit person would give up." No one wants to tell a patient in a life-threatening state that they have to catch their breath before they can continue patient care.
Beyond the basic definition of physical fitness, you should be familiar with its three general components:
- Body composition;
- Cardiorespiratory endurance; and
- Musculoskeletal fitness.
Body composition refers to the body_s relative amounts of fat and is usually expressed as a percentage of total body weight.Cardiorespiratory endurance is usually defined as the ability to perform rhythmic or dynamic exercise involving large muscle groups for prolonged periods.Musculoskeletal fitness includes strength, muscular endurance and flexibility.
These components can be measured separately, and each assessment will provide information regarding your fitness level in each specific category. For example, an individual may score well in cardiorespiratory fitness but poorly in flexibility, or poorly in cardiorespiratory fitness but well in muscular strength. Bettering your overall physical fitness improves your ability to perform under physical stress and reduces your risk of developing chronic lifestyle-related diseases, such as diabetes, coronary artery disease and hypertension.
Time to Assess Yourself
It's good to have an idea of where your physical fitness levels are prior to beginning a new exercise program so you can gauge your progress. An effective fitness assessment will address each of the components of health-related physical fitness, and a practical assessment will allow you to complete it with relative ease. Before beginning, make sure to obtain your physician's clearance, especially if you're over 45 (men) or 55 (women) years old.
Two practical approaches to assessing body fat are waist circumference and body mass index (BMI) tests. Waist circumference is a simple way to determine the presence of abdominal obesity, which can lead to increased risk of heart disease and premature death. A cloth tape should be held evenly at the level of the umbilicus to obtain the measurement. According to published norms, you're at high risk if your waist measurement is greater than 35 (women) or 39 (men).
Another simple method for determining if you're at a healthy weight is by looking at a BMI chart; the National Heart, Lung, and Blood Institute has an easy-to-follow Web site that helps you calculate your BMI and compare it with established norms (www.nhlbisupport.com/bmi). This is a height-weight measurement and doesn't consider body composition. But most Americans, EMS personnel included, are usually overweight because of fatty, not lean, tissue. The normal range for BMI is about 20Ï25 kgm.
Cardiorespiratory fitness can be determined by using field tests that predict VO max. VO max is the maximum amount of oxygen that can be utilized by the body, often expressed in units of milliliters of oxygen per kilogram of body weight per minute (mLkg min). In practical terms, someone who has a VO max of 60 mLkg min will perform better in a race than someone who has a VO max of 45 mLkg min, all else being equal.
A Walk-Jog Formula
The good old 1.5-mile walk-jog test that's been used to assess the cardiorespiratory fitness of firefighter and law enforcement candidates throughout the country is also an excellent predictor of VO max for EMS personnel. This test is as simple as mapping out a 1.5-mile course on flat terrain and timing your completion of the course. Use the following formula: VO max (mLkg min) = 3.5 + 483/time
In this formula, time is rounded to the nearest hundredth of a minute. For example, if it took you 10:24 (10 minutes, 24 seconds) to complete the course, the conversion of seconds to hundredths would be .40 (24/60). With the time 10.40, your estimated VO max would be 50 mLkg min.
If you haven't exercised on a regular basis for more than six months and/or have a lower fitness level, you can try the Rockport one-mile walk test instead. Go to www.jems.com/jems and browse the January issue to read about how to do it.
Although most of us have entertaining EMS stories about when we realized what kind of shape we were in, performing these tests will give you an objective measure of fitness status relative to two components: body composition and cardiorespiratory fitness. In the future, we'll discuss methods for assessing musculoskeletal fitness, the last component, along with other fitness guidelines to get you ready to respond to those calls that require some muscle and some sweat.JEMS
- Clarke HH:Application of Measurement to Health and Physical Education.
Prentice Hall, Inc: New Jersey, 1976.
- Bray GA: "Don_t throw the baby out with the bath water."The American Journal of Clinical Nutrition. 79(3):347Ï349, 2004.
- American College of Sports Medicine:ACSM_s Guidelines for Exercise Testing and Prescription, 7th Edition. Lippincott, Williams & Wilkins: Maryland, 2006.
John Amtmann, EdD, NREMT-B, is a professor of Applied Health Science at Montana Tech of the University of Montana in Butte. He_s an EMT with A-1 Ambulance in Butte, an ACSM certified preventive and rehabilitative exercise specialist and an NSCA certified strength and conditioning specialist. Contact him atJAmtmann@mtech.edu.