Does Exercise Make Us Hungry?

There has been much debate about the effect of exercise on appetite and energy intake.  Although some scientists have proposed that exercise stimulates appetite; most studies do not support this finding. 

A recent study published in Medicine & Science in Sports & Exercise⁴ examined the effect of walking on appetite and food intake.  In the study, subjects participated in two different trials – an exercise and a nonexercise (control) trial.  One day subjects walked for 60 minutes on a treadmill with some mild shortness of breath but were still able to hold a conversation.  On another day, they came to the lab at the same time of day but did not exercise (control trial).  Subjects were offered an “all you can eat” buffet style meal two hours after exercise and again at five hours after exercise. When subjects did not exercise they were offered the same buffet meal at the same time of day.  Subjects also rated their appetite every 30 minutes.

The results showed that after a 60-minute brisk walk subjects did not increase the amount of food they ate for the next seven hours compared to the control trial.  In fact, exercising subjects had a 439 calorie deficit after accounting for the amount of food consumed.  There was also no difference in the fat or carbohydrate content of meals on the exercise vs. nonexercise days.  Researchers also measured levels of a hormone (ghrelin) produced in the stomach which is known to increase hunger.  They found no difference in the hormone levels or ratings of appetite on the exercise compared to nonexercise trials. 

This study supports the findings of other researchers¹ that moderate intensity exercise does not increase appetite.  With regard to high intensity aerobic exercise, studies^2,3 tend to show that appetite is suppressed for a brief period after 60 minutes of treadmill running.  Another study² also reported a brief suppression of appetite after 90 minutes of resistance training. 

Dieting alone to lose weight can be brutal.  So why not go for a bigger calorie deficit by adding exercise to your diet program.  Exercise yields lots of health benefits like improvements in blood pressure, cholesterol, and blood sugar levels.  Plus, exercisers have lower all-cause death rates.  It's time to get moving!     

1.  Blundell, J.D., and King, N.A. (2000). Exercise, appetite control, and energy balance. Nutrition, 16(7-8), 519-522.

2.  Broom, D.R., Batterham, R.L., King, J.A., Stensel, D.J., Batterham, F.L., and King, J.A. (2009). Influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin, and peptide YY in healthy males. Am J Physiol Regul Integr Comp Physiol, 296(1), 29-35.

3.  Broom, D.R., Stensel, D.J., Bishop, N.C., Burns, S.F., and Miyashita, M. (2007). Exercise-induced suppression of acylated ghrelin in humans. J Appl Physiol, 102(6), 2165-71.

4. King, James A., Wasse, L.K. Broom, D.R., and Stensel, D.J.. (2010) Influence of brisk walking on appetite, energy intake, and plasma acylated grehlin. Med & Sci in Sports & Exerc, 42(3), 485-492.

Training on unstable surfaces such as stability balls and balance boards continues to gain popularity. Exercises on unstable surfaces are often promoted to improve balance and challenge core stability more than traditional resistance training using free weights and machines. However, scientific proof that training on unstable surfaces is superior to traditional resistance training performed on stable surfaces, such as a bench, is lacking. Given that most activities of daily living are performed on stable rather than unstable surfaces, it is important to determine whether exercising on unstable surfaces transfers to improvements in activities performed on stable surfaces.

One group of researchers designed a study to answer the following questions:

1. Can you lift more weight on stable surfaces compared to unstable surfaces?

2. Which requires more core stabilization – lifting on a stable or unstable surface?

3. What effect does lifting an unstable load (dumbbells vs a barbell) have on strength and core stabilization?

A study by Kohler and his associates1 measured the amount of resistance that could be lifted during an overhead press using stable vs unstable loads (barbell vs dumbbells) and stable vs unstable surfaces (weight bench vs stability ball). Thirty subjects with at least one year of resistance training experience volunteered to participate in the study. Each subject performed an overhead press under four conditions:

1.  Using a barbell seated on a bench (no back support) – stable load, stable surface

2.  Using dumbbells seated on a bench (no back support) – unstable load, stable surface

3.  Using a barbell seated on a Swiss ball – stable load, unstable surface

4.  Using dumbbells seated on a Swiss ball – unstable load, unstable surface
Researchers measured strength for each exercise during a 10 RM (Repetition Maximum) shoulder press exercise. The test measures the amount of resistance that could be lifted 10 times to failure during each exercise condition. This allowed researchers to determine if subjects were able to lift equal amounts of weight when using unstable loads and surfaces. Next researchers measured the activity of the core muscles while subjects performed 3 sets of each exercise.

Subjects lifted the most weight when using a barbell seated on a stable surface and the least when lifting dumbbells (unstable load) on a stability ball (unstable surface). This demonstrates that as the load and/or the surface becomes unstable that the maximum amount of weight lifted decreases. If an individual’s goal is to increase strength, the reduced ability to load an exercise when using unstable loads (dumbbells) or surfaces will limit strength gains.

Muscle activity in the abdominals was higher during exercises performed on stable surfaces. This suggests that the ability to lift more resistance on stable surfaces requires more abdominal musculature. For the back muscles, activity was signficantly higher when lifting stable loads (barbell) on both stable and unstable surfaces.    These findings may, however, be specific to the overhead press and may not reflect core muscle activity for other exercises like the bench press or rowing exercises.

TAKE HOME MESSAGE: The results of this study emphasize the need to include some traditional strength training exercises into your exercise program to maintain and improve muscular strength. Although this study did not measure balance or ability to perform activities of daily living, another study by Spennewyn2 reported that training on unstable surfaces can improve balance. Until more research is available regarding the effects of training on unstable surfaces, it is a good idea to incorporate a mix of traditional resistance training, in addition to exercises on unstable surfaces into your exercise program. This is especially important if the goal of the program is to improve muscular strength.

1. Kohler, J.M., Flanagan, S.P., & Whiting, W.C. (2010). Muscle Activation Patterns While Lifting Stable and Unstable Loads on Stable and Unstable Surfaces. Jour Stren & Cond Res, 24(2), 313-321.

2. Spennewyn, K.C. (2008). Strength Outcomes in Fixed Versus Free-Form Resistance Equipment. Jour Stren & Cond Res, 22(1), 75-81.

You may be aware that March is Colon Cancer Awareness Month. Among cancers that affect both men and women, colorectal cancer is the third most common diagnosed cancer and the second leading cause of cancer-related deaths in the United States. According to the American Cancer Society, almost 150,000 new cases of colorectal cancer were diagnosed and approximately 50,000 people died from the disease last year. Despite these statistics, unlike some cancers, colorectal cancer is highly preventable and can be detected early through proper screening. And what do you think one of the most important prevention tools is? That’s right—physical activity.

In 2009, a review published in the British Journal of Cancer combined the data from 52 published studies on physical activity and colon cancer1. It was determined that the most physically active participants were 24% less likely than the least active to develop colon cancer. And the good news is this pattern held true for both lifestyle and structured physical activity.

This may not be surprising to some as regular physical activity has been shown to reduce the risk of many chronic diseases. But what many may not realize is that for those diagnosed with colon cancer, regular physical activity may decrease the risk of cancer recurrence and death2,3. In the long running Nurse’s Health Study, women who engaged in moderate physical activity (i.e. brisk walking) six days per week for about an hour per day reduced their risk of colon cancer-related death by 61% and 57% for all causes of mortality, when compared with women who rarely exercised2. And maybe even more remarkable was that even if the women began exercising after their diagnosis, they reduced their risk of colon cancer-related death by 52%. So the expression “it’s never too late to start” definitely applies here. Another study, this time with both men and women who had been diagnosed with stage III colon cancer, showed similar results3. With about six hours per week of walking, just like the previous study, there was a 49% decrease in the risk of getting colon cancer again.

So once again, the evidence shows the amazing power of physical activity. The American Cancer Society recommends that adults get at least 30 minutes of moderate or vigorous physical activity on 5 or more days of the week. Moderate or vigorous activity for at least 45 minutes on 5 or more days of the week may lower your risk for colorectal cancer even more. And as a reminder, screening is the most powerful tool for preventing colon cancer.

To learn more about colon cancer visit the American Cancer Society.

1KY Wolin et al. Physical activity and colon cancer prevention: a meta-analysis. British Journal of Cancer. 2009; 100(4): 611-616.

2Meyerhardt JA, Giovannucci EL, Holmes MD, et al. Physical activity and survival after colorectal cancer diagnosis. Journal of Clinical Oncology. 2006; 24(22):3527–3534.

3Meyerhardt JA, Heseltine D, Niedzwiecki D, et al. Impact of physical activity on cancer recurrence and survival in patients with stage III colon cancer: findings from CALGB 89803. Journal of Clinical Oncology. 2006 Aug 1; 24(22): 3517-8.

Whether you are making an effort to become a regular exerciser or you’ve noticed a decrease in your motivation to maintain a routine, take the following self assessment and see if your current exercise choices are really the "Best Fit" according to your schedule, likes and dislikes, social goals, and fitness goals.

Directions: Read the following statements and circle or select yes (Y) or no (N) regarding your agreement with the statement.

1. Y N I have well defined fitness goals.

2. Y N I know how to reach my fitness goals.

3. Y N My fitness program includes all 3 elements of fitness: cardiovascular, strength training and flexibility.

4. Y N I have access to the equipment, gym, or the classes I need.

5. Y N Time is always an issue regarding making time for exercise.

6. Y N I travel regularly and I find it difficult to work out.

7. Y N My job requires that I have lots of interaction with people daily.

8. Y N I am bored with my work out.

9. Y N I feel like exercising is "work" and not much fun.

10.Y N I have been exercising regularly for less than 3 months.

Now read the following paragraphs to get insights, and suggestions to attain a "Best Fit" exercise routine that fits your current lifestyle, attitudes, responsibilities, time demands, likes and dislikes, and social needs.

Sign up for group exercise classes if your assessment revealed any of the following: boredom, time crunch, lack of a balanced work out, and/or a job that lacks much people interaction Here is why: Group Exercise Classes provide a stimulating atmosphere with music and high energy leadership that puts some fun into the work out. Also, many classes offer a total body work out, so your time is effectively used and every component of fitness is addressed. Furthermore, you can benefit from new moves or experience new exercises. You may use fitness machines or apparatus that you otherwise wouldn’t have tried. You will be challenged afresh mentally, physically, and emotionally. Lastly, you will have a social network that supports your efforts and motivates you to keep exercising.

If your assessment revealed a big demand from others due to the nature of your work, consider choosing exercises that allow for "me time". For example for the cardiovascular segment of your workout, select a machine with a built in TV and get lost in a favorite show, sports programming, or relaxing comedy. Or you can opt to listen to your i-tunes while doing cardio, strength training and flexibility. Run, walk, or cycle outside and enjoy the quiet of nature and get refreshed, revitalized.

Lastly, if your assessment revealed a lack of well defined fitness goals, how to reach those fitness goals, travel concerns, and/or you have been exercising regularly but for less than 3 months, consider hiring a qualified personal trainer for 6-12 sessions. The trainer can assess your current level of fitness, accelerate your progress towards goals, address weaknesses you might otherwise ignore, and make sure you are on track. With their help you have a connection with a professional that you may consult from time to time to keep you motivated, safe, and moving forward.

Prochaska, J, Norcross, J, and DiClemente, C. Changing For Good: A Revolutionary Six-Stage Program for Overcoming Bad Habits and Moving Your Life Positively, Avon Books, Inc. NY. 1994.

As most individuals recognize, physical inactivity has been shown to increase the number of deaths from all-causes, as well as from heart disease and cancer. But what about individuals who meet the physical activity recommendations but spend most of the day sitting?  Does all that sitting have a negative impact on health?

A study performed by Dr. Katzmarzyk¹ and his associates (2009) examined the effects of prolonged sitting on all-cause and cardiovascular death rates in individuals who exercised and those who did not.  The researchers collected information about daily activities including time spent sitting in over 17,000 individuals.  They followed the subjects for an average of 12 years measuring the number of deaths and the cause.

Not surprising, researchers reported the highest death rates in persons who spent most of the day sitting.  However, all-cause and heart disease death rates were also higher in persons who spent more time sitting even if they met the recommended physical activity requirements.  In fact, death rates were similar in exercisers and nonexercisers who spent most of their day sitting.  

Researchers are studying the effects of excessive sitting on the body.  Some of the negative effects include Type 2 diabetes, metabolic syndrome, obesity and cardiovascular disease.  Scientists believe that an active lifestyle may provide different health benefits than occur with exercise alone, providing further protection against heart disease.    

This research highlights the need to reduce sedentary behaviors by spending more time standing, walking, and climbing the stairs.  Low intensity activities like cleaning, ironing, walking the dog and yard work are excellent ways to add activity to your day while completing chores on your ”to-do" list.  For additional health benefits, focus on increasing lifestyle activities over and above structured moderate to vigorous intensity exercise bouts. 

1.  Katzmarzyk, P.T., Church, T.S., Craig, C.L., & Bouchard, C. (2009). Sitting time and Mortality from All Causes, Cardiovascular Disease, and Cancer. MSSE, 41(5),998-1005.

The Super Bowl is over. The Saints are Super Bowl champs! Did you get your fill of football food and commercials? The conclusion of football season for many of us means that spring is just around the corner. If you believe Punxsutawney Phil who saw his shadow, however, we are in for 6 more weeks of winter. In past blogs we have discussed the decline in physical activity levels of our nation’s youth and some of the potential reasons. A recent study published in the International Journal of Behavioral Nutrition and Physical Activity has found that inappropriate clothing is another factor that may limit or even prevent young children’s outdoor play¹. Researchers looked at 49 child-care providers from 34 child-care centers in Cincinnati to determine why children’s physical activity levels vary across the centers despite experiencing the same weather conditions. They were shocked to find that having just a few children inappropriately dressed prevented an entire day-care class from going outside to play. Clothing that affected outdoor play included:

•    Inadequate weather protection (i.e. no coat/hat/gloves in the winter)
•    Unstable footwear (i.e. flip flops)
•    “Nice” outfits (i.e. clothing that had to be treated with care)
•    Jewelry (i.e. items that have the potential to get caught in equipment)
•    Ill-fitting clothes (i.e. too lose or too tight)

The teachers that were interviewed speculated reasons as to why parents may dress their children inappropriately which included:
•    Forgetfulness
•    A “car culture”
•    A hectic morning routine
•    Limited income
•    A child’s preference for a favorite piece of clothing
•    Parents concern with child’s appearance
•    Parents failing to understand the importance of outdoor play

These findings are a major cause for concern as 75% of children ages 3 to 6 spend time in childcare.

There are many organizations who are trying to raise awareness of the decline in the level of physical activity of our children and encourage a reversal of this trend. One example is the U.S. Forest Service and the Ad Council who we highlighted last June in our blog titled The Other You. Since we were talking football earlier, another organization trying to boost kid’s activity levels is the NFL. The NFL has launched the NFL PLAY 60 campaign designed to tackle childhood obesity by getting kids active through in-school, after-school, and team-based programs. They even have an online child-targeted outreach on NFLRUSH.com. As part of this campaign, we here at The Cooper Institute have teamed up with NFL PLAY 60 to launch FITNESSGRAM® into schools and after-school community organizations. FITNESSGRAM® is the premier fitness assessment tool designed to educate families and students on their health related-fitness levels and to encourage healthy behaviors for a lifetime.
To learn more about NFL PLAY 60 and FITNESSGRAM® click on the links above. And remember to think about your child’s clothes before sending them to school or daycare. You may just be affecting a whole classroom’s chance to play!

¹ Copeland, K., Sherman, S., Kendeigh, C., Saelens, B., and Kalkwarf, H. Flip flops, dress clothes, and no coat: clothing barriers to children’s physical activity in child-care centers identified from a qualitative study. Int. J. Behav. Nutr. Phys. Act. 6: 74, 2009.

It's that time again... shopping for school supplies, clothes, and healthy foods that your kids won't throw away in the cafeteria. Start this year off right by substituting the boring turkey on white bread, apple, and baggie of pretzels with some of these fun, good-for-them foods:

Sandwich Substitutes

• Whole-grain* pita pocket stuffed with tuna or chicken salad (made with a little mayo, dried cranberries, and finely chopped nuts)
• Rainbow pinwheels made by spreading cream cheese on a whole-grain* tortilla; topping it with roast beef or turkey, thin carrot strips, and a few leafy greens; rolling it up; and cutting it into slices
• Whole-grain* bagel (or 2 whole-grain mini bagels) with small containers of peanut butter and jelly for dipping
• Egg salad on a whole-grain* English muffin
• Ham, cheese, and a dollop of brown mustard on a whole-grain* bun

Note: Keep these foods cold by putting an ice pack or frozen drink (100% fruit juice box or water) wrapped in paper towel in the lunch box or brown bag.

Snack Substitutes

• Baked tortilla chips and salsa
• Whole-grain* crackers (like whole-grain goldfish-shaped cheese crackers) and hummus
• Reduced-fat (2% milk) cheese stick
• Colorful veggie spears (sliced carrots, red/green peppers, cucumber) with light ranch dip
• Fruit kebabs (grapes, melon, berries)

Sweet Substitutes

• Trail mix (dried fruit, nuts, whole-grain* cereal, and small chocolate pieces)
• Kiwi fruit (slice in half and serve with a spoon)
• Banana or berry bran muffin

Share your ideas!

*The words "whole-grain" should be number one on the ingredient list. 

During these tough economic times Americans are cutting costs - everywhere. While some cuts may not directly affect one's health like less traveling or delaying a move, others do. Cuts like eating out less and less money spent on sedentary activities (e.g., movies, video games) might actually improve one's health. But cuts to healthy activities (as described below) can backfire by increasing future doctor visits and money spent on healthcare.

But, Americans are doing it anyway... in a survey of 1,000 people conducted by the American Heart Association:¹

• 57 percent said the economy has affected their ability to take care of their health.
• 32 percent have made a change in the last six months to save money, such as delaying preventive care appointments, not taking medications or skipping the dentist.
• 25 percent of those with gym memberships have cancelled in the previous six months.
• 42 percent plan to make changes in the next six months that may impact their health, such as buying fewer fruits and vegetables.

So what's a struggling person to do? Learn ways to cut costs AND continue healthy behaviors! Here are some ideas:

• Walk - it's free; find a route near your home or workplace (www.mapmywalk.com) to fit in some moderate-intensity walks each day.
• Eat more meatless meals; beans and nuts are cheaper than chicken, beef, and fish.
• Mow and rake your own lawn and clean your own house; it takes time, but it's good for your budget and your health.
• Brown-bag breakfast and lunch whenever possible; restaurant foods are overpriced and overportioned; tasty sandwiches, salads, and sides are easy to make at home.  
• Walk or run errands - literally; even if you don't live near the store or post office you can still park somewhere in-between the places you need to go and walk or run instead of driving to each store; it'll save you on gas and give your body its needed exercise. 
• Buy whatever produce is on sale at the store each week; in season produce is fresh, tasty, and affordable.

What are your healthy cost-cutting ideas?

¹Americans skimp on healthy activities in bad economy. http://americanheart.mediaroom.com/index.php?s=43&item=737. Accessed June 1, 2009.

Wondering how often you should weigh yourself to determine whether you're in calorie balance?

Some research has shown that people who have lost weight and weigh every day are less likely to gain back the weight. But, daily weigh-ins may not be helpful for everyone. The advantage to daily weigh-ins is that it is easy to catch small weight gains and get back on track with eating and physical activity behaviors, if needed. On the other hand, daily weigh-ins may frustrate some dieters who are working hard but see increases on the scale. A scale can't differentiate between gains or losses in fluid, muscle, or fat. If someone interprets a one-pound weight gain as fat, when it is really just water retention, he/she will likely be disappointed. And this can lead to unhealthy weight behaviors like skipping meals, avoiding the scale, or giving up completely.

A recent study published in the Canadian Medical Association Journal¹ found that biweekly (every other week) weigh-ins with a nurse were effective for weight loss maintenance in a large group of women. In this study, women were randomized to either an intensive support group (one-on-one sessions with a nutritionist and exercise trainer) or nurse support group (brief weigh-in visits and phone calls alternating weeks), and one of two diets - high carbohydrate or high monounsaturated fat. Compliance with both the intensive support group and bi-weekly weigh-ins was high, and weight loss maintenance did not differ between support or dietary groups. Thus, researchers concluded that weigh-ins every other week with a nurse, or maybe even another healthcare provider are effective for weight loss maintenance.

According to the National Weight Control Registry, an ongoing survey of over 5,000 men and women who have lost at least 30 pounds and maintained weight loss of at least 30 pounds for 1 year or more, weekly weighing is very important. In fact, 75% of the participants report weighing themselves at least once per week.

So what's the answer? Weighing once per week is probably enough. Weigh at a scheduled time each week with similar amounts of clothing. If the scale reads high, think about your behaviors over the past week and if you had any lapses. If the scale reads low, congratulate yourself for achieving a negative calorie balance. If you think you need to be held accountable to someone other than yourself, consider calling a friend or healthcare provider (or sending him/her an e-mail) each week with your current weight.

How often do you weigh yourself?

¹Dale, K.S. (2009).Determining optimal approaches for weight maintenance: a randomized controlled trial. Canadian Medical Association Journal. 180(10).

From time to time we expose the calorie content of certain foods to enable you to make educated decisions when eating out. While some restaurants choose to (or are required to) provide this information, many don't . And without knowing how many calories you are consuming, how will you know if you've run over your daily calorie allowance?

This week we're revealing the min, the max, and the Ay Dios Mio! (oh my gosh!) of calories found in various Mexican foods. We'll also provide some simple strategies for cutting calories when eating Mexican fare.

Lower Calorie Chioces*: Chicken tortilla soup; 1 to 2 grilled chicken, beef or fish soft tacos; chicken salsa fresca

Higher Calorie Choices*: small (4 slices) grilled chicken, steak or cheese quesadillas; grilled vegetable fajitas; 1 to 2 chicken, beef or fish crispy tacos or enchiladas 

Extremely High Calorie Choices*: Chicken, steak or shrimp fajita platter; fajita or taco salad with dressing; chicken, beef or vegetable enchilada platter; chicken or beef burritos; chicken or beef chimichangas; chicken or fish with creamy red chile sauce

*Calorie content provided by nationwide chains. Food items do not include rice and beans. Lower calorie choices have 500 calories or less per typical serving; higher calorie choices have between 501 calories and 800 calories per typical serving; and extremely high calorie choices have over 800 calories per typical serving.

More Ways to Lighten your Mexican Plate:

• Tacos and taco salads - ask for cheese and dressing to be served on the side 
• Fajitas - ask for less oil and no butter when frying meat, fish and veggies 
• Enchiladas and burritos - order grilled chicken or fish
• Beans - order black beans or charro (pinto) benas instead of refried beans
• Rice - ask for a side of salad or grilled vegetables instead
• Condiments - use pico de gallo or salsa as a topping instead of sour cream
• Tortillas and tortilla chips - limit them and ask for corn tortillas instead of flour
• Alcoholic beverages - margaritas typically have 250-500 calories; think before you drink! 
• Platters - avoid combos and mega-platters; instead, order a la carte