Measuring Exercise Intensity: RPE & Talk Test

In addition to heart rate, there are two other methods of measuring exercise intensity: rate of perceived exertion (RPE) and the talk test.

Rate of Perceived Exertion
Perceived exertion is how hard an exercising individual feels they are actually working. RPE was originally based on a 15-point scale that began at 6 and ended at 20. This scale was found to be hard to understand by exercisers so a new 10 point scale was developed that begins at zero and ends at 10. During exercise, either scale can be used to gauge the intensity of exercise. The RPE scale is considered a reliable guide as it has a strong linear relationship to heart rate.


Old RPE Scale





New RPE Scale

The Talk Test
The talk test is also used to evaluate exercise intensity during cardiorespiratory exercise. The ability to engage in conversation during exercise represents work at or near a steady rate. When an exerciser can comfortably converse while exercising, their intensity is low to moderate. At the point at which they can just barely respond in conversation the exerciser is at a moderate to vigorous intensity. The talk test also corresponds to heart rate, as it becomes more difficult to engage in conversation the higher the participant's heart rate.

Using heart rate, RPE, or the talk test during exercise can help ensure that you are exercising at the correct intensity for your fitness level and overall goals. Exercise intensity should be measured at regular intervals during all exercise sessions.

Source: AFAA Fitness: Theory & Practice, 5th ed.

Holiday Weight Gain in College Students

Thanksgiving marks the beginning of the holiday season. The next five weeks are filled with family, friends, finals, and lots of food! It's no wonder that the average American packs on a few pounds during the holidays. I believe that college students are even more susceptible to weight gain over the holidays for several reasons.

First of all is Thanksgiving. For some students this is the first time home since August and you're dying for some home cooking. And who doesn't love a good Thanksgiving feast? Most people overindulge at Thanksgiving with foods that are full of butter, sugar, and fat. Enough about Thanksgiving, I'll expand more on that in my next post.

After Thanksgiving college students return to school and are faced with final projects, final papers, and final exams. This is a very stressful time especially for the first year students who are experiencing their first final exam week. Finals time often means late nights at Willy T, skipped workouts, and increased stress levels. All of these are contributors to weight gain. Most students who stay up late to study or finish an assignment will end up consuming an extra 250-1000 calories than they normally would each day. These calories usually come from energy drinks, snacks, and added meals. Skipping workouts means that calories are not being burned, and spending more time studying decreases daily calorie burn. Instead of consuming extra calories during finals, most students should actually cut back on calories because of decreased activity. And stress often leads to eating when you're not hungry. Stress eating combined with the distraction of studying can lead to some very dangerous mindless eating. Ever grab a bag of something to snack on while studying, and next thing you know the entire bag is gone!? That's mindless eating. I'll post more about mindless eating before we get into finals week.

Once winter break arrives college students head home to their family and friends. Just like Thanksgiving, Christmas break is filled with lots of food and drinks that can lead you to consume extra calories. Christmas cookies, pies, and other pastries are fine in moderation, but you should not eat multiple servings each day around Christmas. Also be careful of liquid calories. Many of the warm, creamy beverages we love when the weather is cold can pack about 350 calories per 12 oz. serving. Drink just 10 servings and you will have consumed enough calories to gain one pound.

Not only do we often consume extra calories over winter break, but many college students also get out of their regular exercise routine. When you're at school it's fairly easy to go to the Johnson Center to workout. When you head home it's not always as easy to access a fitness facility, but you can find other ways to stay active without a gym. Go back to the basics and do some calisthenics in your living room. Jumping jacks. high knees, and butt kicks will still burn calories. If it happens to snow where you are over winter break, go shovel some snow. Not only will you burn about 400 calories an hour, you'll also have happy parents!

Don't let yourself be someone that gains weight over the holidays. Stay active and make smart dietary choices! I'll post several more times about staying healthy over the holidays, so stay tuned!

Measuring Exercise Intensity: Target Heart Rate

When performing cardiovascular exercises (running, swimming, biking, etc.) it is important to measure your exercise intensity at various points in your workout. The Aerobics and Fitness Association of America recommends measuring intensity at three points during an aerobic workout or group fitness class.

1. Five minutes into the workout to determine if you are exercising within your target range.
2. At the completion of the most intense portion of your exercise session.
3. At the completion of the aerobic cool-down to determine if you have recovered sufficiently.

There are three main ways to measure exercise intensity during aerobic exercise: heart rate, rate of perceived exertion, and the talk test.

Target Heart Rate
Measuring exercise intensity using target heart rate is the most widely used method during aerobic exercise. Using target heart rate will allow you to exercise at a safe and effective level. Working in your target heart rate rate during aerobic exercise will also allow you to use oxygen efficiently and make fitness gains. Exercising at a level underneath your target heart rate will not be sufficient enough to burn maximal calories or attain higher levels of cardiovascular fitness. Meanwhile, exercising above your target heart rate will put you into an anaerobic zone where your body is no longer using oxygen for exercise. This level is ineffective and unsafe for most exercisers especially if maintained for an extended period of time.
Target heart rate is usually represented in percentages of your maximum heart rate. Your working heart rate range should depend on your current fitness level.

• Beginner: 50-60% of maximum heart rate
• Intermediate: 60-70% of maximum heart rate
• Advanced: 75-85% of maximum heart rate

When beginning a fitness program, you should start in the 50-60% range and remain there for 2-3 weeks. At that point if you feel ready to workout at a higher intensity aim for the lower end of the 60-70% range and gradually work your way through the range for approximately the next 6 months. Working in intervals is also a great way to experiment with exercising at a higher intensity. Increase your intensity to a higher level for 1-2 minutes, then return to a lower intensity for 2-3 minutes. Gradually increase your exercise duration at the higher level every week.

Calculating Target Heart Rate
There are multiple ways to calculate your target heart rate. The most commonly used formula and the easiest to calculate is the Historical Formula, while the Karvonen Formula is more accurate because it factors in resting heart rate.
Using the Historical Formula

1. Estimate your heart rate max (220 - age)
2. Determine your working heart rate range from above (beginner, intermediate or advanced)
3. Multiply the bottom number in the range by your maximum heart rate
4. Multiply the top number in range by your maximum heart rate
5. Your target heart rate range is the answer to #3 - the answer to #4

An Example using the Historical Formula
Determine the working heart rate range for a 22-year old intermediate exerciser

1. 220 - 22 = 198
2. working heart rate range = 60-70%
3. 60% x 198 = 118.8
4. 70% x 198 = 138.6
5. The exercisers target heart rate range is 118.8 to 138.6 beats per minute

Using the Karvonen Formula

1. Determine your resting heart rate *see below*
2. Estimate your heart rate max (220 - age)
3. Calculate your heart rate reserve (heart rate max - resting heart -ate)
4. Determine your working heart rate range from above (beginner, intermediate or advanced)
5. Multiply the bottom number in the range by your heart rate reserve, then add your resting heart rate
6. Multiply the top number in range by your heart rate reserve, then add your resting heart rate
7. Your target heart rate range is the answer to #5 - the answer to #6

An Example using the Karvonen Formula
Determine the wokring heart rate range for a 22 year old intermediate exerciser with a resting heart rate of 70 beats per minute

1. Resting heart rate = 70 beats per minute
2. 220-22 = 198
3. 197-70 = 128
4. 60-70%
5. (60% x 128) + 70 = 146.8
6. (70% x 128) + 70 = 159.6
7. The exercisers target heart rate range is 146.8 to 159.6 beats per minute

Determining Your Heart Rate
To check your heart rate, for resting or working, begin by finding your radial artery on the outside of your wrist. Make sure to use your first two fingers (not your thumb) to locate your pulse. Begin with the count of "1" and continue counting the beats for 15 seconds. Multiply this number times 4 to determine your heart rate. When determining your resting heart rate, it is best to check it first thing in the morning before you get out of bed. If this isn't possible, sit quietly for 10 minutes before checking it.

Once you determine your working heart rate, compare this number to your target range. If your target heart rate is within your range, then you're right on track! If the number is below your range, increase the intensity by increasing your speed, incline, or resistance. If the number is below your range decrease the intensity by decreasing your speed, incline, or resistance.
Remember to try to check your heart rate at least 3 times during your workout as I mentioned earlier. Checking your heart rate periodically during aerobic exercise can help to make your workouts more effective and set you on the right path toward meeting your fitness goals. I will post about the other two methods of measuring exercise intensity in the upcoming week.

Sources: AFAA Fitness: Theory & Practice, Sparkpeople