Cold Weather Training Means Options!
Elaine Gonya, Licensed Athletic Trainer
Aurora Sports Medicine Institute
During winter weather, many road-running faithful are challenged to find suitable cross-training options that have comparable cardiovascular benefits to their everyday running routines. Whether you choose to brave the elements or retreat to the gym, there are a number of alternatives that offer similar cardiovascular values to running.
Metabolic Equivalents (METs)
An often-dismissed energy expenditure concept for runners, who maintain fitness over the winter (vs. training for an event), is the use of Metabolic Equivalents (METs). Using a mathematical formula, Metabolic Equivalents are calculated from one's resting metabolic rate, body weight, duration and intensity of exercise. MET, or the standard metabolic equivalent, is a unit used to estimate the amount of oxygen used by the body during physical activity.
One (1) MET equals the energy (oxygen) used by the body at rest (i.e., sitting quietly or reading a book). The harder your body works during the activity, the more oxygen is consumed and the higher the MET level. The largest limitation in exploring this type of energy expenditure is using the guidelines in existence that estimate METs per specific exercise.
If an athlete wanted an exact calculation of METs during activity, he/she would need to complete a VO2 Max test to determine oxygen usage during exercise and then incorporate this figure into a MET formula. However, during non-competition training, if ball-park figures will meet your needs, it's simple to use the estimated figures published by the American College of Sports Medicine (ACSM) or the American Heart Association (AHA) to determined METs. Charts with this information are available on-line for your reference.
The MET Calculation
Activity that burns three (3) to six (6) METs is considered moderate-intensity physical activity. Activity that burns more than six (6) METs is labeled vigorous-intensity physical activity.
Remembering that one metabolic equivalent represents an adult's energy expenditure per minute when sitting quietly, if an adult walks at three (3) mph for 30 minutes on a flat hard surface (i.e., moderate intensity walking), he/she would expend 3.3 METs (i.e., 3.3 times more energy than at rest). Using this information to calculate MET-minutes: 3.3 METs x 30 minutes = 99 MET-minutes.
If he/she jogs at five (5) mph for 20 minutes on the same surface (i.e., vigorous-intensity jogging), the expenditure is: 8 METs x 20 minutes = 160 MET-minutes.
Moderate-intensity walking done five (5) days/week would result in:
Five days @ 99 MET-minutes = 495 MET-minutes/week.
Completing vigorous-intensity jogging three (3) days/week:
Three days @ 160 MET-minutes = 480 MET-minutes/week
To determine your weekly MET levels, simply multiply the corresponding MET levels and time (in minutes). For cardiovascular fitness, aim for a weekly minimum goal of 450-750 MET-minutes. Higher intensity runners should meet or exceed a 750 MET-minutes goal.
Previous studies have established these MET levels:
- Walking - very brisk: 6.3 METs
- Walking/hiking - moderate pace with grade with/or/no light pack (10 lbs or less): 7 METs
- Hiking - steep grades with pack of 10 to 42 lbs.: 7.5 to 9 METs
- Jogging - 5mph: 8.0 METs
- Jogging - 6 mph: 10 METs
- Jogging - 7 mph: 11.5 METs
- Deep water running: 8 METs
- Snow shoveling: 5 to 7 METs
- Cycling: 8 METs
- Cross-country skiing:
- Slow: 7 METs
- Fast – 5 to 8 mph: 9 METs
- Swimming: 8 to 11 METs
- Ice skating: 6 to 9 METs
- Snow-shoeing using broken-in trail: 8 METs
Runners, who utilize fitness club memberships during winter months, often choose to cross-train with swimming and deep water running, elliptical machines, treadmills, spin bikes, cardio classes, and resistance training. By using MET calculations to replace running with alternate cardio choices, you're able to reduce, or possibly eliminate, some of the excessive pounding your ankles, knees and hips take during warm-weather activities.
Cold-weather Activity Options
Those who choose to embrace Mother Nature during the cold months, often find the challenges of running inconsistently shoveled sidewalks and roadways, jumping over piles of snow, and skidding through patches of ice – enjoyable. There are other fantastic cardio options beyond this "winter triathlon of cross-training": Snow shoveling, cross-country skiing, ice skating, deep-snow running (i.e., 6 – 10 inches), Nordic walking, and snow-shoeing.
Recently, more study has been done on the cardiovascular benefits of snow-shoeing, placing this activity close to running in terms of improving cardiovascular endurance and VO2Max levels. Replacing a runner's training regimen with snow-shoeing has been shown to increase run speeds and endurance. Snow-shoeing workouts are most effective in at least eight (8) inches of snow.
When choosing a snowshoe for exercise, identifying your primary "use" is important – will you be traveling over broken-in trails, exploring the backcountry or doing speed workouts? Be sure to pick a reputable store and sales person to help you determine the proper size, style and construction material to best suit your activity needs. Modern snow-shoes are made of light metal or plastic and offer a raised toe for increased maneuverability. Aerobic snow-shoes are a newer option to the sport – small and light, they help to facilitate faster cardiovascular workouts – however, they are not meant for backcountry snow-shoeing. With sizing, a common formula is to match each pound of body weight with one square inch of snow-shoe surface per snow-shoe.
As the winter season approaches, when it comes to activities, think outside-the-box! Why not challenge yourself to log calorie expenditures in a different way? Or, how about incorporating some exercise options that offer a less-intensive impact on your joints. Go ahead – dust off those ice skates, grab a shovel and help a neighbor with their walk, try some deep-snow running, or even invest in a pair of snow-shoes. You may find that your talents run much deeper than straight-forward running down the same ole' road!
For more information on training in cold weather or other sports medicine topics, call the Aurora Sports Medicine Hotline™ at (414) 219-7776 or (800) 219-7776.