Cardiorespiratory fitness reflects integration of several body systems, including the cardiovascular, respiratory and musculoskeletal systems. It helps optimize heart health and is an important predictor of adverse health outcomes, including premature death, heart attack and heart disease. Indeed, the American Heart Association suggests that cardiorespiratory fitness should be measured as a vital sign during a doctor’s visit. Yet, cardiorespiratory fitness declines with age, which is thought to result from changes to heart structure and function that are further influenced by factors we can (e.g., physical activity) and cannot (e.g., heredity) change.

Interestingly, much of what we know about changes in cardiorespiratory fitness with increasing age comes from cross-sectional studies. While cross-sectional studies provide important preliminary evidence to support further research, they cannot tell us how cardiorespiratory fitness changes in the same person over time, or if the rate of decline increases as we get older. While a handful of longitudinal studies have been conducted, few young adults and people of color were included.

Understanding changes in cardiorespiratory fitness from early adulthood to midlife may be particularly important. Young adults experience several important life events, such as starting a career and/or family that might temporarily or permanently change behaviors that influence cardiorespiratory fitness. Young adults may discount the long-term benefits of regular physical activity to optimize cardiorespiratory fitness in exchange for immediate rewards, like extra time in the day. Also, there is a lack of cardiorespiratory fitness data in population-based samples that include early adults. This may be due to prioritizing study questions that specifically examine the importance of cardiorespiratory fitness to reduce risk of adverse events, which typically occur later in life.

Our study, published in the July 2022 issue of Medicine & Science in Sports & Exercise_®, sought to address this important research gap using data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. In addition to describing age-related changes in cardiorespiratory fitness from early adulthood to midlife, we also examined if there were differences in these changes by factors present in early adulthood. The CARDIA cohort, which began in 1985, includes 5,114 Black and white men and women aged 18-30 years recruited at baseline from four clinical centers in the U.S. The cohort has been re-examined every 2-5 years and a symptom-limited maximal graded exercise test protocol was included at baseline as well as the year 7 and year 20 follow-up exams. Data collection for the year 35 follow-up exam is ongoing and includes a fourth symptom-limited maximal graded exercise test.

The most important takeaway from this study was that declines in cardiorespiratory fitness occurred within the first few years of early adulthood. The rate of decline through midlife was more accelerated than previously reported in the Baltimore Longitudinal Study of Aging, ranging from 4.6% from ages 20-25 to about 10% every 5 years from ages 30 to 50. Also, these declines varied based on sex, race and other factors present in early adulthood. For example, physically active participants and those who consumed alcohol but never smoked had higher cardiorespiratory fitness in early adulthood and less of a decline in fitness through midlife. In contrast, participants who experienced overweight/obesity or reported fair or poor reported health status had lower cardiorespiratory fitness during early adulthood which persisted through midlife.

Together, these findings suggest that early adulthood is a critical life-course stage to intervene in unhealthy behaviors to optimize cardiorespiratory fitness. We simply cannot put off maintaining a healthy lifestyle for later in life. With routine follow-up of adverse events, CARDIA is well-positioned to add to what we know regarding the importance of optimizing cardiorespiratory fitness across adulthood.

Kelley Pettee Gabriel, Ph.D., M.S., FACSM, FAHA, is a professor of epidemiology at the University of Birmingham at Alabama with undergraduate and graduate training in exercise science, clinical exercise physiology and epidemiology. Dr. Gabriel actively collaborates with several large observational studies, including CARDIA, to examine the timing of physical activity and cardiorespiratory fitness on subsequent risk of disability and disease using a life-course framework. She currently serves as a principal investigator on four National Institutes of Health-funded studies.

Viewpoints presented in SMB commentaries reflect opinions of the authors and do not necessarily represent ACSM positions or policies. Active Voice authors who have received financial or other considerations from a commercial entity associated with their topic must disclose such relationships at the time they accept an invitation to write for SMB.

Public health is having a moment right now, and the fitness industry must rise to the occasion. The truth is, the fitness industry is uniquely positioned to improve many public health outcomes through promotion of regular physical activity. Positioning physical activity as part of the health care continuum — as an accessible, integral part of a healthy lifestyle for all people — is a big part of the path forward. And, we need high-performing fitness professionals to lead the way!

Fitness professionals are the “boots on the ground,” translating decades of exercise science and sports medicine research into practice. In many ways, they are the heart of the field: They change lives every day, and sometimes every hour. They have the knowledge to help those new to exercise and the skill to train elite performers. They change behaviors and impact quality of life. So, what does it take to excel as a fitness professional? I’ve outlined five must-have qualities below.

1. Credibility 

To me, credibility is founded upon the trifecta of formal education, certification and practical experience. Earning an industry-leading certification helps you establish a strong foundation of key exercise science concepts while also requiring you to stay up to date by pursuing continuing education. Practical experience — or application of the knowledge you’ve gained through your education and credentialing — is critical for success. If you’re newer to the industry, seek out practical experience by programming for a friend or family member, or shadowing an experienced professional,

2. “Hungry-yet-Humble” Attitude

Recall your most influential teacher or coach. Chances are, their passion and hunger to improve your life is imprinted in your memory. Fitness professionals who have this same, genuine “it” factor can make a big splash. In a service profession, though, humility is key. Be confident in what you know; understand the limits of your knowledge; and be humble enough to seek guidance, take feedback or refer out to other professionals as needed.

3. A Zest for Learning

I’m a firm believer in intentional learning. Learning must not stop when you enter the job market — but, as your life gets busier with coaching clients and teaching group classes, you must be intentional with the time you set aside to learn. Maintaining your certification(s) through continuing education helps you prioritize study time, and I encourage you to try some of the following ideas too: If you’re into social media, follow accounts like ACSM to see what free, evidence-backed resources are available. Consider attending a virtual or in-person conference within the industry. And take workouts that differ in format and delivery style than the ones you coach — I guarantee you will learn something by putting on your “client hat” and remembering what it feels like to learn something new.

4. Skilled Communication

Effective communication helps in all aspects of life. But when you’re working 1:1 with clients or delivering a workout to a large group of people, communication takes center stage. Clear, confident delivery of instructions and education, with the ability to flex toward the communication and learning styles of the client(s) in front of you, can make or break the group exercise experience. Mastery of vocal inflection, and incorporation of nonverbal communication like gestures and body language, are also key to building trust and delivering a great product.

5. Empathy

Fitness journeys are personal and often emotional, so the ability to show empathy — or understand and share the feelings of another — is critical for success in the fitness industry. Purposeful development of skills like reflective listening, asking open-ended questions and motivational interviewing can help improve your ability to show empathy to your clients. Properly placed empathy can build trust, and that trust is often what keeps clients coming back for more.

Honorable mention goes out to “practicing what you preach,” or modeling the behavior you wish to inspire in others. After all, fitness professionals will be best equipped to serve their communities — and improve public health outcomes — if they have more energy, less fatigue, improved sleep quality, improved mood, more endurance and stronger hearts. And you know what helps with that? Exercise.

Additional Resources: 
Blog | A Day in the Life of a Group Exercise Instructor
Blog | How Being Dual Credentialed Can Improve Your Hiring and Salary Potential

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Don’t miss the second edition of ACSM’s Resources for the Group Exercise Instructor — available this summer! This updated edition is fully aligned with the eleventh edition of ACSM’s Guidelines for Exercise Testing and Prescription. It is an essential resource for undergraduate exercise science programs, students in pre-professional programs and those independently preparing for the ACSM Group Exercise Instructor (ACSM-GEI) certification. This new edition of ACSM’s Resources for the Group Exercise Instructor highlights the skills needed to effectively lead group exercise in gyms, studios, recreational facilities and clubs.

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Rachelle Reed has a B.A., M.S. and Ph.D. in exercise physiology, along with an ACSM-EP and NASM-CNC. She brings forth expertise in body composition, metabolism, physical activity measurement and behavior change, along with over a decade of group coaching experience. Dr. Reed aims to translate research about physical activity and behavior change into practice, bridging the gap between academia and the fitness industry through her work. She joined Orangetheory Fitness in 2019, where she is currently senior director of health science and research. Prior to joining Orangetheory, Rachelle was the kinesiologist for Pure Barre, a brand owned by Xponential Fitness. She lives in Watkinsville, Georgia, with her husband, Sam, their two kids (AJ, 4, and Madison, 5 months) and their dog, Roy.

Whether you are a seasoned fitness professional or a new trainer entering the field, it’s more important than ever to be versatile and competent in working with a variety of clientele. As our industry shifts with the needs and demands of the public, we want to be educated and experienced working with clients one on one, in small groups and large groups, or even in an online environment. Being a hybrid fitness professional not only makes you more hirable for an employer but also gives you the skill set and resources to know how to adapt workouts so they are effective, regardless of how much direct feedback you are able to provide.

My certifications as a group fitness instructor and a certified personal trainer have worked hand in hand to help me build my career. Not only have I had the ability to reach more individuals, but I have also improved upon coaching skills that serve me in every aspect of my career. Group fitness techniques have improved my ability to adapt workouts and develop effective cueing, and have served as a built-in referral system to grow my career as a personal trainer and beyond.

The challenges of teaching more than one person at a time are different from one-on-one training. You need to be cognizant that you are working with different fitness levels, different demographics and different learning styles. In the same class you can have someone who is taking their very first step into fitness right alongside someone who is looking for a class to take their fitness to the next level. Both individuals are looking to you for guidance and motivation. Improving group fitness knowledge enables you to identify these different levels and learn how to coach and adapt your workouts to meet the needs of everyone in the room.

Teaching group fitness has improved my skills with cueing and exercise demonstration. When working in a group, you are unable to use tactile cueing, and it can be difficult to stop or slow down the movements to work on technique. For this reason, it is imperative that you are able to use alternative cues that can help participants understand how an exercise should look and feel for them. With group fitness experience, I have developed a toolbox of effective cues that I use both with classes and with personal training clients. No matter how much direct contact I have with each client, I am better able to coach them to success due to my group exercise experience.

Any group fitness instructor can tell you that their class members are loyal. Within this setting you are able to build trust and rapport with participants so they feel connected and comfortable with the fitness professional. For those who are hoping to build a personal training career, this can be a valuable resource for finding potential clients without the need to market or advertise. Simply deliver a great group fitness class and allow those who attend to see how knowledgeable you are and how much you have to offer.

Being a hybrid fitness professional shows you have the knowledge, skills and abilities to work in more than one environment. This not only has helped build my confidence when working with clients, but it has made me more a more desirable candidate for employment since I am able to serve the facility in more than one department. Many of the gyms I have worked in have been able to benefit from hiring me as a hybrid fitness professional because I am competent in both environments and assist the two different departments in working together. Looking into the future, you may decide on a management role; possessing dual certifications will allow you to understand the needs and benefits of both departments, what skills to look for when hiring new candidates, and how to further the mission of the company.

As I look back, I can definitely say that holding both a group exercise instructor and personal training certification provided me opportunities that have advanced my career and earning potential.

Additional Resources: 
Blog | A Day in the Life of a Group Exercise Instructor
Blog | 5 Skills of High Performers in the Fitness Industry

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Don’t miss the second edition of ACSM’s Resources for the Group Exercise Instructor — available this summer! This updated edition is fully aligned with the eleventh edition of ACSM’s Guidelines for Exercise Testing and Prescription. It is an essential resource for undergraduate exercise science programs, students in pre-professional programs and those independently preparing for the ACSM Group Exercise Instructor (ACSM-GEI) certification. This new edition of ACSM’s Resources for the Group Exercise Instructor highlights the skills needed to effectively lead group exercise in gyms, studios, recreational facilities and clubs.

Candice Campbell, M.S., CSCS, CES, ACSM-CPT, is a full-time lecturer in the Department of Kinesiology at California State University, Long Beach, where she teaches in the Fitness and Integrated Training Bachelor of Science degree program. She has been a certified personal trainer for 15 years, with a specialized focus on clients with unique health considerations. She is the program director at the Shore Strength Lab, a small group-training facility in Long Beach, California, and has taught group fitness for over 14 years. She has also enjoyed participating in fitness research and program development for several health and fitness companies, and currently serves on the ACSM Certification and Registry Board Certified Personal Trainer Committee.

I always laugh when people assume that teaching group exercise means getting paid to exercise. So far from the truth! Any group instructor knows this is a fallacy. From the outside it looks easy to do — a little like a duck gliding along the in water, you don’t see the little legs churning. Still, most people don’t see all the work that goes into teaching group fitness classes. Getting certified is an essential start, but then there’s all the ongoing specializations and continuing education, as well as practice and preparation.

Keeping up with the changes and growth in the industry is a job in and of itself! When I started teaching in 1986, I got certified to teach aerobics, and that was it. And back then it was high-impact aerobics — now there is a myriad of different classes group instructors can learn how to teach. But I digress … I’m simply setting the stage to make a point: In today’s environment, to be successful, a group instructor needs to be a highly skilled professional. So, let’s examine one day in my life.

My Wednesdays start super early, since I have a 40-minute commute to a 6 a.m. treadmill-running class, followed by a 7 a.m. high-intensity interval training (HIIT) class in the main studio. Then I rush home to set up my home studio for a 10:30 a.m. virtual class. No big deal, really! Of course, on paper it looks straightforward, but the reality is not so simple.

The first two classes are for younger, presumably healthy, fit populations in a health club setting, whereas the later virtual class is for the active aging, a group of men and women whose ages range from 60 to 88, many of whom have a host of different health conditions, such as macular degeneration, osteoporosis, cardiovascular disease and osteoarthritis. I need to use a whole different skill set for this third group, and I don’t mean just the technology, although the class involves a computer, lights, a webcam, screen sharing, a microphone and all the rest of it.

My Wednesday preparation starts the week before, on Thursday, when I have time to practice the running classes I will coach the following Wednesday. Then on Tuesday there’s additional prep, such as designing and planning the other two classes and one more review of the treadmill run. So, when the alarm goes off at 4 a.m. and I’m grabbing my cup of coffee and having some quiet time to be mentally prepared, my day of teaching is all ready to be presented. As they say, if you fail to plan, you plan to fail. Class prep is everything!

Once I get to the gym, I check the app to see who’s signed into class and review so I can remember their names and if they have any injuries or limitations, likes, dislikes and specific goals. I get to the treadmills early so I can greet people as they arrive. Coaching the class with a stopwatch, I carefully follow the designed plan and help my participants manage the intensity, length and speed of the intervals. Forty-five minutes later, after the cooldown, stretch, high-fives and fist bumps, I’m ready to go into the main studio to teach the HIIT class. Here’s where I lay out equipment and get music playing to set the stage so I can greet people as they come in. The class is high intensity, so I keep it fun and doable, allowing people to self-select the level to work at. Even though it’s HIIT, I still teach multi-level. Forty-five minutes later, I’m heading home for breakfast and to set up for the virtual class.

Lights, camera, action! It all starts again, but now with a different set of goals for a very different population. Keeping people engaged and building a sense of community is critical for the success of the class. Some people don’t have their camera on, so it’s harder to communicate. But watching those who do is essential. This is what makes the class competitive in the virtual world: the community and careful interactive communication you provide make all the difference. Fifty minutes later, after cooldown and stretch, I then film some moves from my class to post on social media. After breaking down the lights and putting everything away, it’s time to plan Thursday’s classes and prep for the rest of the week.

A well-prepared group instructor makes teaching look effortless. But the secret sauce is in the preparation, starting with certification and continuing education and building from there —not always the easiest career, but for me, one of the most rewarding! Even after 36 years of teaching, I feel just as excited and passionate, so when that 4 a.m. alarm goes off on Wednesday, I’m looking forward to seeing how I can make a difference. 

Additional Resources: 
Blog | 5 Skills of High Performers in the Fitness Industry
Blog | How Being Dual Credentialed Can Improve Your Hiring and Salary Potential

---

Don’t miss the second edition of ACSM’s Resources for the Group Exercise Instructor — available this summer! This updated edition is fully aligned with the eleventh edition of ACSM’s Guidelines for Exercise Testing and Prescription. It is an essential resource for undergraduate exercise science programs, students in pre-professional programs and those independently preparing for the ACSM Group Exercise Instructor (ACSM-GEI) certification. This new edition of ACSM’s Resources for the Group Exercise Instructor highlights the skills needed to effectively lead group exercise in gyms, studios, recreational facilities and clubs.

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Keli Roberts, ACSM-EP, has been recognized for many prestigious awards in the fitness industry. In 2003, she was named the IDEA International Fitness Instructor of the year. In 2005, Keli was awarded the Best Female Presenter and in 2008 she received the Lifetime Achievement OBOW award and in 2007 she was inducted into the National Fitness Hall of Fame. Keli is an ACSM-EP and holds certifications through AFAA and ACE as a GFI, HC and CPT. Moreover, Keli is an SCW Faculty Member, a Schwinn Senior Master Trainer and an Ambassador for Ryka.

Physical activity is recognized as one of the key healthy lifestyle behaviors that reduces the risk of developing dementia late in life. Physical activity requires increased rates of respiration. Thus, in areas with high levels of air pollution, physical activity may increase exposure to particulate matter and gases that are linked with higher risk of developing dementia. Previous work has suggested that engaging in physical activity in areas with high air pollution may attenuate some physical activity-related health benefits. To date, however, no research has examined the potential interaction between physical activity and air pollution on the risk of developing dementia.

In our study, published in the July 2022 issue of Medicine & Science in Sports & Exercise_®, we used the largest sample collected to date (n = 35,562) that includes objectively measured physical activity (via wearable accelerometers). Our goal was to determine whether air pollution exposure modifies the relationship between physical activity and incident dementia. We found that, overall, increased physical activity is associated with reduced risk of developing dementia. However, for two types of air pollution, PM_2.5 (particulate matter with diameters less than 2.5 microns) and PM_{2.5 absorbance}, (a measure of black carbon), the beneficial effects of physical activity on incident dementia are eliminated at high air pollution exposures. Air pollution exposure in this sample is comparable to regions where pollution levels fall within World Health Organization and United States Environmental Protection Agency guidelines for health and welfare. Our findings suggest that even moderate levels of air pollution impact physical activity-related brain benefits.

We think there are several key takeaways from this study that have implications both for future research as well as for broader discussions of policy and public health. First, both epidemiological research and multicenter interventions examining exercise and brain health may be impacted by differences in air pollution across geographic locations. These environmental interactions may moderate the true impact of physical activity and exercise on the brain, and researchers should consider taking environmental data into account in their analyses and research design. Second, we hope this work spurs future research into how best to minimize physical activity-related risks of air pollution at the individual level (e.g., use of high-quality masks, optimal times of day for physical activity and improvements in indoor air quality in gyms).

However, our most important message is that there is only so much an individual can do to minimize the impacts of air pollution on their own exercise patterns. Thus, our work is part of a broader literature that calls on researchers to advocate for improvements in air quality at local, national and international levels. We know that disparities exist, both in how air pollution exposure differs across socioeconomic circumstances and in individuals’ ability to avoid exposure due to occupational physical activity. Thus, it is incumbent on us all to help reduce air pollution at a societal level. Only by working together can we have a broad impact on everyone’s ability to equally reap the brain benefits of physical activity.

David Raichlen, Ph.D., is a professor in the Human & Evolutionary Biology Section of the Department of Biological Sciences at the University of Southern California. He studies the evolutionary origins of human physical activity and applies this perspective to physical activity epidemiology and exercise physiology in living humans. With a specific focus on the role of physical activity in reducing dementia risk, he combines methods from epidemiology, cognitive neuroscience, exercise physiology and biological anthropology to bring evolutionary principles to work on improving brain health in modern human populations.

Viewpoints presented in SMB commentaries reflect opinions of the authors and do not necessarily represent ACSM positions or policies. Active Voice authors who have received financial or other considerations from a commercial entity associated with their topic must disclose such relationships at the time they accept an invitation to write for SMB.