QUIZ 2: PAGE 118 Every day, consumers are bombarded with bogus claims about the benefits of quick workouts. Magazine covers offer the "60-second ab exercise" that will "peel off 7 pounds" or tout faster work- outs to "burn double the fat in half the time." Fitness infomercials claim that just minutes a day will "get you ripped, guaranteed" and boast testi- monials from users who have (supposedly) lost more than 50 pounds, or three dress sizes, with Research just 3 minutes of exercise a day. While the appeal of such claims is obvious, suggests that marketing grossly exaggerates the physical trans- formation that is possible from short workouts. encouraging However, the fact that exaggerated claims sell products points to an important reality: nonexer- the inactive to cisers are often intimidated and overwhelmed by the evidence-based guidelines for physical embrace any activity. The most widely accepted guideline- physical supported by the American College of Sports Medicine (ACSM), the American Heart activity— Association, the U.S. Department of Health and Human Services and the World Health even at levels Organization—recommends that adults engage in a minimum of 30 minutes of moderate-inten- that fall short sity physical activity 5 days a week. This is in addition to ordinary, everyday activity. To lose of industry weight or sustain a weight loss, even more exer- cise is required. ACSMs latest recommendation, guidelines— based on a thorough analysis of existing evidence, may offer suggests that significant weight loss is unlikely with less than 250-300 minutes of moderately a bevy of vigorous exercise per week, or about 1 hour a day, 5 days a week (Donnelly et al. 2009). >> benefits.Baby Steps # JL By Kelly McGonigal, PhD By Kelly f : 2011 IDtA Fitness Journal
Many in the fitness indus- diet, alcohol use, menopausal status, hormone use and family try see 30-60 minutes a day as history of heart disease. a reasonable goal, and yet only The cardiovascular benefits of low levels of exercise are not 11% of Americans currently fully understood. However, there is evidence that even small meet the minimum recom- doses of exercise have a positive influence on metabolism and mendation (Schoenborn & cardiovascular physiology. For example, physical activity reliably Adams 2010). A large section reduces blood pressure—not just in the long term, as the cardio- of the population isnt even vascular system adapts to exercise and people become more fit- trying. According to the most but immediately, after a single bout of exercise (MacDonald recent survey data, 33% of 2002). This effect, dubbed "postexercise hypotension," appears American adults never exer- to last for several hours after physical activity and is especially cise and 55% never engage in pronounced among those with hypertension. vigorous activity (CDC 2010). A study from the University of Connecticut and Hartford These numbers only increase Hospital asked. Does a short workout provide the same blood with age, as the health conse- pressure benefits as a longer workout (Guidry et al. 2006)? The quences of being inactive- researchers recruited 45 sedentary men to test the effects of two such as cardiovascular disease sessions of indoor cycling (15 minutes vs. 30 minutes) on blood (CVD)—also climb. pressure. The men were randomly assigned to one of two in- To sedentary adults, 30-60 tensities (light = 40% VO^max, and moderate = 60% VO2max). minutes a day can seem Each participant then completed 3 days of study; a short-work-impossible. They may feel that they cant find the time or that out day, a long-workout day and, for comparison, a nonexercisehealth challenges or physical pain prevent them from being phys- control day. Exercise took place between 8:00 AM and 11:00 AM,ically active for that long. These nonexercisers are most likely and the participants blood pressure levels were tracked through-to be tempted by the promise of benefits from shorter workouts. out the day.But can smaller doses of exercise lead to any real change? Compared with control days—when participants did not exer- This article reviews the evidence that even short sessions of cise—both the 15- and 30-minute exercise sessions led to lastingexercise—5-15 minutes a day—have very real benefits for phys- reductions in blood pressure over the subsequent 9 hours.ical and mental health. While fitness professionals must steer Interestingly, the shorter dose provided the same benefit as theclear ot unrealistic claims that such short doses can "transform longer dose, and the two intensity levels led to equivalent reductions.your body" or lead to significant weight loss, there is good rea- Its worth noting that the participants in this study were over-son to encourage baby steps among the most reluctant and over- weight, mostly middle-aged men, with below-average fitness, anwhelmed nonexercisers. If we cant convince sedentary average body mass index (BMI) of 29.2 and high-normal to stageindividuals to embrace the industry ideal, we can encourage them 1 hypertension—exactly the kind of people who might beto start small, which will still improve their quality of life. interested in the health benefits of exercise, but who might feel overwhelmed by having to fit in 30-60 minutes per day. TheImproving Heart Health reduced-blood-pressure benefit observed in this study wasIn a 2001 landmark report, the Womens Health Study revealed immediate; the men did not have to "get in shape" first or achievethe results of a longitudinal study of almost 40,000 women, aged any particular titness standard. Based on their findings, Guidry45 years or older, in the United States and Puerto Rico (Lee et and colleagues suggested that short doses of low-intensity exer-al. 2001). Participants were observed for an average of 5 years. cise, especially when performed in the morning (and, ideally,The report examined whether physical activity levels at the again in the afternoon), could provide significant cardiovascu-beginning of the study predicted who developed CVD over the lar health benefits to a sedentary, aging population.next several years. The researchers found a classic dose- Another study looked at longer-term changes in physiologyresponse relationship, with more physical activity providing a and supported the idea that 15-20 minutes of exercise a day cangreater protective effect against CVD. But the amount required improve cardiovascular health (Lippincott et al. 2008). Seventy-to get a significant benefit was quite small. As little as 60 min- two sedentary employees, aged 22-62, participated in theutes of walking per week—less than 10 minutes a day, or a sim- National Heart, Lung, and Blood Institutes "Keep the Beat" pro-ple stroll around the block—was associated with significantly gram. The program gave employees outlines for 15-minute car-reduced CVD risk. In fact, among women who reported no reg- diovascular and strength training workouts they could do in theular vigorous exercise, women who walked at a light to moder- National Institutes of Health (NIH) campus fitness centers. It alsoate pace for at least 1 hour a week had half the risk of women offered tips on fitting short bursts of exercise into the workday—who did not walk regularly. This effect held even when the for example, by taking the stairs or walking around campus.researchers statistically controlled for factors such as smoking. The studys first observation was that employees did indeedso July-August 2011 IDEA Fitness Journal
become more active; adding a 15-minute workout was a feasi- researchers were able to track and record every time a participantble change that previously sedentary employees could fit into broke a sedentary period by standing or taking a single step. Thetheir workday. Program participants averaged 98 minutes of participants also kept a log of any moderate to vigorous physicalexercise per workweek, equivalent to one 15-minute fitness cen- activity, so researchers could separate the benefits of standhig upter workout and a few minutes of extra activity each day By the troni the benefits of regular exercise. The participants who tookend of the 3-month study, the exercise had paid off. Employees a higher number of breaks from being sedentary had smallerin the program showed significant improvements in several waist circumferences, as well as lower blood glucose and triglyc-measures ot fitness and CVD risk, including increased peak VO2, éride levels. The frequency of stand or step breaks predicted theseimproved eiidothelium function, reduced blood pressure and health measures independent of time spent exercising and totallower cholesterol. sedentary time. In other words, every time a person stood up or took a single step, it contributed to his or her health. It didntMitigating the Effects of Sitting matter how active or inactive that person was.A 15-minute workout may seem to yield impressive benefits, but This research suggests that fitness professionals can crediblythe smallest dose of exercise that can improve cardiovascular recommend even the smallest of behavior changes—such ashealth may be even shorter. A growing body of research suggests standing up every half-hour—to sedentary individuals (see thethat spending long stretches of time sitting is a significant risk sidebar "Recommending the Smallest Dose of Exercise"). Evenfactor tor health problems, independent of whether or not a per- it people are unwilling or unable to commit to a formal exerciseson exercises regularly (Hamilton et al. 2008). More uninter- program, they can fit brief moments of activity into their days torupted sitting is associated with higher waist circumference, support their health.blood pressure, blood glucose, cholesterol and triglycérideslevels. The good news: A study from the University of Improving Psychological Well-BeingQueensland in Brisbane, Australia, found that the simple act While more attention is typically paid to the physical health ben-of breaking a period of sitting with any physical activity was efits of exercise, its effects on mental health are also well estab-associated with a healthier metabolic profile (Healy et al. 2008). lished (Stathopoulou et al. 2006). However, unlike the For this study, 168 adults (mean age 53.4 and mean BMI of dose-response relationship observed for physical health—where27.2) wore accelerometers—a device that measures the bodys a little exercise is good, but more is often better—the latestacceleration—during all waking hours for 1 week. The research suggests that when it comes to psychological well-Recommending stand up and stretch every 30 minutes.the Smallest Find an excuse to take a short walk around the home or workplace once an hour.Dose of Exercise Walk to the farthest bathroom when going to the restroomi Stand and/or walk around the room when talking onLen Kravitz, PhD, senior exercise physioiogist for IDEA, researcher the telephone.and program coordinator of exercise science at the University of Get up and move (or at least stand up!) during everyNew iVlexico, encourages fitness professionals to recommend stand- commercial break while watching television or betweenor-walk breaks to clients whose work, commute or leisure activities chapters/articles while reading. J»require hours of sitting. These suggestions could be helpful: Source: Kravitz 2009^
A Short Dose of Exercise Strengthens Self-ControlImagine this: Youre a participant in study, the researchers wanted to cise can strengthen self-control. Kate Janse Van Rensburg,a scientific study, and youve just know: Could a 15-minute walk The same research team has MSc, lead author of these studies,been put through a challenging before the mental stress test help shown that a 15-minute tread- says, "A single session of exercisemental test designed to stress you people resist the temptation to mill walk reduces cravings tor can reduce the attention-grabbingout The researcher then walks in soothe their stress with chocolate? cigarettes among smokers and power of temptations. Daily ses-with your favorite instant stress All participants were asked to improves concentration in the sions of brief exercise could bereliever: chocolate. The researcher abstain from chocolate for 3 days, face of distractions (Janse Van integrated into any behavioroffers you a variety of chocolate which previous research has shown Rensburg & Taylor 2008; Janse change attempt to help reducebars, asks you to choose your fa- increases cravings (Polivy, Coleman Van Rensburg, Taylor & Hodgson cravings and handle withdrawal."vorite and instructs you to unwrap & Herman 2005). When the partici- 2009; Janse Van Rensburg et al. Clients who are trying to quitit. But before you can savor the pants arrived at the laboratory, half 2009). One study looked at brain smoking, cutting back on caffeine,first creamy mouthful, she tells of them were asked to walk briskly activation among smokers pre- conquering their sweet tooth oryou not to eat it. on a treadmill. These participants sented with images of ciga- changing to a vegetarian diet could Researchers at the University showed smaller blood pressure rettes. After exercise, the brains all benefit from short doses ofof Exeter, England, put 25 choco- increases during both the stressful reward system—which is re- physical activity. Recommendinglate lovers through this mini stress mental task and the self-control sponsible for feelings of desire exercise as a coping strategy fortest as part of a study on exercise test, suggesting that exercise and craving—was less reactive stress and cravings can also trans-and self-control (Taylor & Oliver helped them cope better with both to the images. Another study form working out from a chore into2009). We tend to think of exercise challenges. Exercise also reduced tracked the eye gaze of smokers a source of strength—a motivationas something that requires self- these participants chocolate crav- and found that those who had that could help people stick withcontrol, but psychologists are now ings and urges to eat the candy bar just exercised spent less time exercise in the long run.considering the possibility that it This is just one study demon- looking at smoking-relatedalso increases self-control. For this strating that short doses of exer- images.52 July-August 2011 Fitness Journal
whether short doses of exercise can contribute to lasting changesGet Your in psychological well-being. A 2009 meta-analysis looked, not just at the immediate mood benefits of exercise, but at the longer-termExercise Mood Boost effects on depression (Rethorst, Wipfli & Landers 2009). Researchers analyzed the results of 58 randomized trials andResearch shows that as little as 5 minutes of outdoor physical activity found that, overall, exercise interventions (lasting anywhere fromimproves mood and self-esteem. What can you—and your clients— 4 to 26 weeks) resulted in significant reductions in depression.do in 5 minutes? Once again, shorter workouts yielded the biggest benefit.• Get out of fhe office and head for the ciosest greenery or open sky. Interventions that assigned participants to exercise for fewer• Cue up a favorite song on your i/lP3 piayer and walk or jog around than 30 minutes at a time had significantly larger effects than the block. interventions that assigned longer workouts (e.g., 45-59 minutes• Take your dog outside fo play (and chase fhe toy yourseif). or more than 60 minutes). When researchers compared overall• Do a bif of work in your yard or garden. time spent exercising with degree of improvement, they did not• Sfep oufside for some fresh air and do a few simpie sfrefches. find a linear dose-response relationship. More exercise time did• Challenge your kids fo a race or game in fhe backyard or local park. not translate into bigger improvements. These findings—drawn from a very large number of studies—provide further support tobeing, short doses work as well as, or better than, longer work- the idea that sedentary individuals can reap substantial mentalouts (see the sidebar "Get Your Exercise Mood Boost"). health benefits from short exercise sessions. A recent meta-analysis (Barton & Pretty 2010) reviewed 10 stud-ies that examined how exercise influences psychological well-being. The Benefits of Becoming ActiveAll 10 studies—which collectively observed more than 1,200 partic- The research shows there are substantial benefits to merely mov-ipants—involved "green exercise," or physical activity that takes place ing out of the "sedentary" category. With some outcomes—suchoutdoors. Green exercise includes walking, running, biking, hiking, as overall risk for cardiovascular disease—more activity is bet-swimming, gardening, roUerblading, taking your dog or kids to ter. But for other measures—such as mood—simply becomingthe park or anything that gets you outside and moving. active provides the full benefit. Barton, who analyzed the bene- The researchers were especially interested in what the best fits of green exercise, suggests that health professionals might"dose" of green exercise was for self-esteem and mood. To their think about "quitting" sedentary living as equivalent to givingsurprise, the biggest benefits came from the shortest workouts. up smoking. Any activity—even a short dose of light intensity-"The biggest difference was seen in the first 5 minutes," says Jo will have immediate positive health outcomes. (For evidence thatBarton, PhD, lecturer in sports and exercise science at the exercise can help with food cravings, see the sidebar "A ShortUniversity of Essex, England, and lead author of the review. Dose of Exercise Strengthens Self-Control.") Getting a person"Longer amounts do not necessarily equate to greater rewards." out of the sedentary category is a worthy goal, even if it fallsIn fact, a 5-minute session improved self-esteem and mood more short of ideal activity levels.than a workout lasting 10-60 minutes. The only dose that came A 2009 randomized controlled trial led by researchersclose to the psychological benefits of 5 minutes was a whole day at Louisiana State University demonstrates this point for a wide rangespent being active outdoors—in other words, a green vacation. of physical and psychological outcomes (Martin et al. 2009). This Barton thinks that "5 Minutes a Day" is a great, targeted message 6-month study assigned 430 sedentary, overweight or obese womenfor sedentary individuals who want to experience the benefits of (mean BMI of 31.8) with high blood pressure to one of four condi-being active but feel overwhelmed by the amount of activity recom- tions: a no-exercise control group, and three different exercise groupsmended for weight loss and better physical health. "Five minutes aiming to achieve 50%, 100% and 150% of NIH-recommendedseems achievable," says Barton. "If you can engage them in these physical activity levels, respectively. (In actual reported activity overshorter bouts, once they start experiencing the benefits, they will be the study, this translated into an average of 74,138 and 184 minutesmore likely to participate more frequently, and for longer periods." of exercise per week at an intensity of 50% VO,max.) Cant get outdoors? Indoor exercisers need not despair. While The researchers measured changes in many dimensions ofa blue sky and green leaves might enhance the mood benefits of quality of life, including physical functioning, general health,exercise, you dont need an inspiring view to get a psychological mental health, social functioning and vitality. Exercise improvedboost from working out. One study compared the benefits of all of these outcomes over the course of the 6-month study.indoor cycling at 60% V02max for 10,20 and 30 minutes (Hansen, Importantly, all three exercise groups improved, while the con-Stevens & Coast 2001). All three exercise sessions increased par- trol group did not. There was a clear dose-response relation-ticipants energy and decreased their fatigue and negative mood. ship for physical and social functioning, with minimum exerciseHowever, these benefits reached their peak at 10 minutes, and there (averaging 10 minutes a day) producing some improvements, butwas no significant benefit to working out longer. more exercise (up to an average of 26 minutes a day) leading to A quick mood boost is good, but its also important to consider even greater improvements. But for general health, mental health J u l y - A u g u s t 2011 iüCA F i t n e s s J o u r n a l S3
Perhaps the most interesting tlnding of this study is that all of the benefits were independent of weight loss. The average weight loss in the exercise groups over the 6-month period was small (2-3 pounds) and did not vary by exercise condition. But even when the researchers compared the outcomes of women who »- lost weight with those who maintained or gained weight, there was no relationship between weight loss and any of the posi- tive outcomes. Other studies—including the "Keep the Beat" program that increased workplace activity and led to improved titness and cardiovascular health—have reported similar find- ings. The improvement of health does not require weight loss; and often, the two do not go together. This finding is particularly important because it points to a current tension within the fitness industry. We know that many, if not most, clients turn to exercise because they want to lose weight. And while there is growing evidence to support the ben- efits of 5-15 minutes of exercise a day for currently sedentary in- dividuals, this dose falls far short of what research suggests is required to lose a significant amount of weight. At the same time, few sedentary individuals seem willing to invest the time needed to lose weight or maintain weight loss. The fitness industry is in a perfect position to make inroads with the population most resistant to exercise. One way to do this is by encouraging nonexercisers to commit to as little as 5 min-and vitality, the benefits of the smallest dose were equivalent to utes a day. To make use of the growing evidence supporting shortthose of the two larger doses. Simply transitioning from a seden- workouts for the sedentary, fitness professionals must becometary lifestyle to any level of exercise enhanced every aspect of the comfortable shifting their focus—and their clients focus—awaywomens quality of life. from losing weight as the sole goal of exercise, and toward other The Ultimate Personal Trainer Software Suite Exercise, Fitness Assessment, Nutrition, Meal Plans, Scheduling, Billing, Retention ManagemenI : maker nutritionhnaker • Schedule trainers, clients, classes • Assess daily calorie requirements • Print dietitian designed meal plans • Perform billing/revenue reporting One • Marketing tools Integrated • Analyze diet and eating habits • Retention management Suite • Print meal plan shopping list or f XPERT ^ Four Separate Programs FiTness Maker Create exercise handouts • Maintain fitness assessment results Create fitness programs • Provide physiologic age service Use for post-rehab • Perform health risk screens Email programs • Print complete fitness reports For free demo call 800-750-2756 or download your free demo at www.BioExSystems.com July-August 2011 IDl:A Fitness Journal
Copyright of IDEA Fitness Journal is the property of IDEA Health & Fitness, Inc. and its content may not becopied or emailed to multiple sites or posted to a listserv without the copyright holders express writtenpermission. However, users may print, download, or email articles for individual use.