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.

Drink Water!

Did you know that more than half of your body wight is actually liquid? Unless your throat feels parched, you probably give little thought to water. Yet this clear, refreshing fluid is one of your body's most essential nutrients. While you may survive for up to six weeks without food, you cannot live longer than a week without water. This fluid helps to keep our body in good working order, cushioning an hydrating our cells, tissues, and organs, transporting nutrients, and eliminating waste from the body. So the saying "You are what you eat" is only half true: You're also what you drink!

Water is the most abundant substance in the human body as well as the most common substance on earth. On average, body weight is 50 to 70% water. The specific percentage varies from person to person, relating to body composition, age, and gender. Body tissues of all types contain water, some more than others. In your body, blood is about 83% water; lean muscle tissue is about 73% water; body fat, about 25%; and bones, about 22% water. So with all of this water in our bodies, you can see why is is an essential nutrient to consume.

Replace Your Losses
In order to maintain a constant temperature and to dispose of waste, your body loses about a half gallon of liquid every day through sweat, exhaled air, and urine. During a strenuous workout you can sweat off up to an additional quart of liquid an hour, and even more on a hot, humid day. All of this water loss needs to be replaced each day. If your body fluids become depleted, you become dehydrated. Extreme dehydration is not a concern if your diet is reasonably balanced, your activity level is not excessive, and you're not stranded in a desert. But minor dehydration is sneakier, because it's not always easy to catch. it can make you feel grumpy and tired and make it hard to concentrate. Minor dehydration can be avoided easily by drinking enough fluids throughout the day. But if you tend to drink liquids only when you're thirsty, you may not be drinking enough of them. Thirst does help you gauge your level of hydration, but it's not quite as reliable a guide as you might assume. By the time you actually feel thirsty, you are actually already dehydrated! So don't wait until you're thirsty to consume fluids, try to consistently drink water throughout the day the remain hydrated.

Thirst in Disguise
It's important to recognize that thirst and hunger are both physiologically and psychologically driven. When you feel hungry between meals, what you may be experiencing is dehydration. Thirst can often disguise itself as hunger, and when you think you're hungry what you may be - even though you don't realize it - is thirsty. the next time you feel a little hungry, try reaching for a glass of water. You may be surprised that the refreshment it brings you turns off that hunger switch until your next meal.

Fluid Consumption: how much is enough?
The amount of water your body needs is based on the amount of energy your body uses. Te recommendation for adults is 1 to 1.5 milliliters of water per calorie of energy expended. That's 1 to 1.5 liters for every 1000 calories. In other words, most people need about 8 to 12 cups of water each day. In healthy people, water intake and water loss balance out. If you should consume too much water than your body needs, your kidneys simply eliminate the excess. When you don't consume enough, your body may trigger a sensation of thirst. As you may know, drinking water is not the only way to get the recommended amount of fluids each day. Most foods contain at least a small amount of water. In fact, some fruits and vegetables are up to 97% water. Consuming these water-containing foods will also help you stay hydrated.

Drinking for Health
To keep your body well hydrated, consume enough water throughout the day. Because milk, juice, and other beverages are mostly water, they count toward your daily water intake, too. Caffeinated beverages and alcoholic beverages, however, are not your body's best sources of water. Caffeine and alcohol at like diuretics, causing the body to lose water through increased urination.

Reduce your carbon footprint and use a reusable water bottle!!

Sources: American Dietetic Association, Nutrition for Dummies, 4th ed.

Shopping for Fresh Produce

Do you find yourself avoiding the produce section at the grocery store because you don't know how to judge an item's quality? This guide from the American Dietetic Association will help you to shop for fresh fruits and vegetables with ease!

Shopping for Fruit
Apples: firm with smooth, clean skin and good color. Avoid fruit with bruises or decay spots.
Apricots: plump with as much golden-orange color as possible. Blemishes, unless they break the skin, will not affect flavor. Avoid fruit that is pale yellow, greenish-yellow, very firm, shriveled or bruised.
Bananas: plump with uniform shape at desired ripeness level. Avoid produce with blemished or bruised skins.
Blueberries: plump, firm berries with a light grayish-purple surface.
Cantaloupes: slightly oval fruit, 5 inches or more in diameter, with yellow or golden (not green) background color. Signs of sweetness include pronounced netting on the rind and a few tiny cracks near the stem end. Smell the melon; it should be noticeably strong and sweet. At home, check for ripeness before you eat it; the stem area will be slightly soft when ripe.
Cherries: plump, bright-colored sweet or sour cherries. Sweet cherries with reddish-brown skin promise flavor. Avoid overly soft or shriveled cherries or those with dark stems.
Grapefruits: firm, thin-skinned fruit, full-colored, and heavy for their size. The best grapefruits are smooth, thin-skinned, and flat at both ends.
Grapes: plump grapes firmly attached to pliable green stems. Color is the best indication of ripeness and flavor. Avoid soft or wrinkled fruits and those with bleached-looking areas at the stem end.
Honeydew melons: melons weighing at least 5 pounds., with waxy white rind barely tinged with green. Fully ripe fruit has a cream-colored rind. When ripe, the blossom end should give to gentle pressure.
Kiwifruit:  choose evenly firm fruit. Will feel slightly soft when ripe.
Lemons: firm, heavy fruit. Generally, rough-textured lemons have thicker skins and less juice than fine-skinned varieties.
Mangoes: usually quite firm when sold and need to be ripened further at home before eating. Avoid those with shriveled or bruised skin. Once ripened, they will give to gentle pressure.
Nectarines: orange-yellow background color between areas of red. Ripe nectarines feel slightly soft with gentle handling, but not as soft as ripe peaches.
Oranges: thin-skinned, firm, bright-colored fruit. Avoid oranges with any hint of softness or whitish mold at the ends.
Papayas: fruit with the softness of peaches and more yellow than green in the skin. Most papayas need to be ripened further after purchase in a loosely closed paper bag at room temperature. Avoid bruised or shriveled fruit at room temperature.
Peaches: creamy or yellow background color. Ripe peaches feel slightly soft with gentle handling. Avoid green, extra-hard, or bruised fruit.
Pears: fruit with firm skin. Pears gradually ripen after picking.
Pineapples: large, plump, fresh-looking fruit with green leaves and a sweet smell. Avoid fruit with soft spots, areas of decay, or fermented odor.
Plums: fruit that is full-colored. Ripe plums are slightly soft at the tip end and feel somewhat soft when handled gently. Avoid fruit with broken or shriveled skin.
Raspberries: firm, plump, well-shaped berries. If soft or discolored, they are overripe Avoid baskets that look stained from overripe berries.
Strawberries: firm, plump berries that are full-colored.
Watermelons: fruit heavy for its size, well shaped, with rind and flesh colors characteristic of the variety. Ripe melons are fragrant and slightly soft at the blossom end. A melon that sloshes when shaken is probably overripe. The stem should be dry and brown, not green. When thumped, you should hear a low-pitched sound, indicating a full, juicy interior.

Shopping for Vegetables
Artichokes: tight, compact heads that feel heavy for their size. Surface brown spots don't affect quality.
Asparagus: firm, brittle spears that are bright green almost their entire length, with tight closed tips.
Beans: slender, crisp beans that are bright and blemish-free. Avoid mature beans with large seeds and swollen pods.
Beets: firm, smooth-skinned, small to medium beets. Leaves should be deep green and fresh-looking.
Bok choy: heads with bright white stalks and glossy dark leaves. Avoid heads with slippery brown spots on the leaves.
Broccoli: compact clusters of tightly closed, dark green florets. Avoid heads with yellow florets or thick, woody stems.
Brussels sprouts: firm, compact, fresh-looking sprouts that are bright green. They should be heavy for their size.
Cabbage: firm heads that feel heavy for their size. Outer leaves should have good color and be free of blemishes.
Carrots: firm, clean, well-shaped carrots with bright, orange-gold color. Carrots with their tops still attached are likely to be freshest.
Cauliflower: firm, compact, creamy-white heads (without brown spots), with florets pressed tightly together. A yellow tinge and spreading florets indicate overmaturity. Leaves should be crisp and bright green.
Celery: crisp, rigid, green stalks with fresh-looking leaves. Avoid celery with limp stalks.
Corn: fresh-looking ears with green husks, most stem, and silk ends free or decay or worm injury. when pierced with a thumbnail, kernels should give a squirt of juice. Tough skins indicate overmaturity.
Cucumbers: firm, dark green cucumbers that are slender but well-shaped. Soft or yellow cucumbers are overmature.
Eggplants: firm, heavy for their size, with taut, glassy, deeply colored skin. Stems should be bright green.
Greens: fresh, tender leaves that are free of blemishes. Avoid bunches with thick, coarse-veined leaves.
Leeks: clean, white bottoms and crisp, fresh-looking green tops.
Mushrooms: blemish-free mushrooms without slimy sports or signs of decay.
Okra: small to medium pods that are deep green and free of blemishes. Pods should snap or puncture easily with slight pressure.
Onions: green onions with with crisp, bright tops and clean white bottoms. Choose firm, dry onions with brittle outer skin, avoiding those with sprouting green shoots or dark spots.
Parsnips: small to medium, smooth, firm, and well shaped. avoid large roots because they may have a woody core.
Peas: small, plump, bright green pods that are firm, crisp, and well filled.
Peppers: bright, glossy, firm, and well shaped. Avoid those with soft spots or gashes.
Potatoes: firm, smooth, with no wrinkles, sprouts, cracks, bruises, decay, or bitter green areas.
Salad greens: crisp, deeply colored leaves free of brown sports, yellowed leaves, and decay.
Sprouts: crisp buds still attached.
Summer squash: yellow squash and zucchini of medium size with firm, smooth, glossy, tender skin. Squash should be heavy for their size.
Sweet potatoes and yams: firm, well shaped, with bright, uniformly colored skin.
Tomatoes: smooth, well formed, firm, not hard.
Winter squash: hard, thick-shelled.

Sodium: A Salty Subject

Although we often refer to salt and sodium as the same thing, they aren't the same substance. Table salt is actually the common name for sodium chloride; 40% sodium and 60% chloride. Sodium is a mineral that naturally occurs in food. Some of the most basic work that your body does depends on sodium: maintaining proper fluid balance, regulating your blood pressure, transmitting nerve impulses, and helping your muscles relax. your kidneys regulate the sodium level in your body.

Sodium Balance

If you're healthy, your body doesn't retain excess sodium - even when you consume more than you need. And excess amounts don't get stored; instead your body rids itself of the extra. Excess sodium passes out through urine and to a much lesser amount, through perspiration. If, for example, you eat foods high in sodium, you may urinate more to get rid of the extra. Then you probably feel thirsty because you lost fluids, too. When your kidneys don't work properly, extra sodium isn't excreted. This causes swelling, often in the face, legs, and feet.

Sodium and High Blood Pressure
You have probably heard that there is a link between sodium intake and high blood pressure. High blood pressure, or hypertension, is a major risk factor for heart disease, stroke, and kidney failure. High blood pressure affects about 1 in every 3 Americans and costs the U.S. over $76 billion for health care costs. There are several risk factors linked to high blood pressure, including family history, overweight, excessive alcohol intake, advancing age, and smoking. So why is attention given to sodium and high blood pressure? Most people aren't affected by excess dietary sodium because their bodies just get rid of the excess. However, many Americans have high blood pressure that's sodium-sensitive. For them, consuming too much sodium contributes to high blood pressure. Likewise, reducing their sodium intake may help to lower blood pressure if it's high.

Sodium in Your Diet
To keep the body running normally, you need sodium. However, few Americans need to be concerned about getting enough. Instead, on average, most adults consume about 4 to 6 grams of sodium daily. That's significantly more than needed. The American Dietetic Association recommends that most Americans limit their sodium intake to fewer than 2400 milligrams of sodium daily. Although you lose sodium and other mineral during exercise, the amount is usually not enough to require additional intake. Most of the sodium Americans consume in their diet is from processed foods; only about 10-25% of sodium intake comes from the salt shaker or sodium-containing ingredients added to food. Low-fat and non-fat food items are often high in sodium to add extra flavor that has been omitted by removing fat. Sodium provides many different functions in processed foods, as it works as a leavening agent, preservative, flavor enhancer, acid controller, and emulsifier.

Types of Salt
When a recipe calls for salt, which one will you use? Most recipes call for table salt, but how does this compare with other types of salt?

• Iodized salt: table salt with iodine added. The human body needs just small amounts of iodine and by adding it to salt, people get enough. An important nutrient, iodine help prevent goiter, which is a thyroid gland condition.
• Kosher salt: coarse grain salt that adds a crunchy texture to some dishes and drinks, such as margaritas.
• Lite salt: salt that is "50-50": half sodium chloride and half potassium chloride. It has less sodium than table salt, but is not sodium-free.
• Pickling salt: fine-grained salt used to make brines for sauerkraut or pickles. Unlike table salt, it has no iodine.
• Popcorn salt: very finely granulated salt that sticks well to popcorn, fries, and chips.
• Rock salt: large, chunky crystals of salt used in a crank-style ice cream maker or as a "bed" for serving foods such as clams or oysters. Not commonly used in recipes, rock salt contains some harmless impurities.
• Salt substitute: made of potassium chloride and contains no sodium.
• Sea salt: salt-either finely granulated or in larger crystals- produced by evaporation of sea water. It has trace amounts of some other minerals that may five it a somewhat different flavor. Even though sea salt is often promoted as a healthful alternative to ordinary table salt, the sodium content is comparable.
• Seasoned salt: salt with herbs and other flavoring ingredients added. Seasoned salt has less sodium than table salt but more than herbs alone.
• Table salt: fine, granulated salt commonly used in cooking and in salt shakers.

Sources: CDC; Nutrition for Dummies, 4th ed.; American Dietetic Association

Prebiotics and Probiotics

Prebiotics and probiotics may promote healthy bacteria, or microflora in your intestines - and perhaps improve your health. Prebiotics stimulate or help activate bacteria growth; probiotics are the live cultures, or bacteria, themselves. Probiotic bacteria taken together with prebiotics that support their growth are called “synbiotics.” Both work together in a synergistic way more efficiently promoting the probiotics’ benefits.

• Prebiotics are non digestive substances such as oligosaccharides (indigestible carbohydrate) in food that promote the growth of normal, healthful bacterial that are already in the colon. Other substances in food, such as dietary fiber, starch, and sugar alcohols, may work as prebiotics, too.
• In order for a food ingredient to be classified as a prebiotic, it has to be demonstrated, that it:
  
  • is not broken down in the stomach or absorbed in the GI tract,
  • is fermented by the gastrointestinal microflora, and
  • most importantly, selectively stimulates the growth and/or activity of intestinal bacteria associated with health and well being
• Probiotics are active cultures, such as some strains of lactic acid bacteria, or foods that contain them, that help reintroduce or change bacteria in the intestine. Lactobacilli and Bifidobacteria in yogurt with live cultures and other fermented dairy foods have probiotic cultures.
• Probiotic cultures may help keep your immune system healthy and help maintain the "good" bacteria in your intestine.
• Probiotics also may help reduce the risk of some health problems
• shorten the duration of diarrhea
• prevent or reduce the severity of colds and flu
• reduce the symptoms of lactose intolerance
• promote a healthy immune system
• help prevent and treat vaginal yeast infections and urinary tract infections
• prevent and treat eczema in children
• decrease the risk of some cancers
• decrease the risk of high cholesterol levels.

Examples of Probiotics and Prebiotics
Class/Component	Source*	Potential Benefit
Probiotics
Certain species and strains of Lactobacilli, Bifidobacteria, Yeast	Certain yogurts, other cultured dairy products, and non-dairy applications	May improve gastrointestinal health and systemic immunity
Prebiotics
Inulin, Fructo-oligosaccharides (FOS), Polydextrose, Arabinogalactan, Polyols—lactulose, lactitol	Whole grains, onions, bananas, garlic, honey, leeks, artichokes, fortified foods and beverages, dietary supplements and other food applications	May improve gastrointestinal health; may improve calcium absorption
Chart adapted from International Food Information Council Foundation: Media Guide on Food Safety and Nutrition: 2004-2006. *Examples are not an all-inclusive list

Sources : Mayo Clinic; International Food Information Council Foundation