For the latest study, researchers at University of Texas Southwestern Medical Center looked at a sample of older people who showed early signs of memory loss and were at risk of developing Alzheimer’s. The less frequently the participants exercised, the weaker the connections in their brain's white matter and the more poorly they performed on a bunch of cognitive tests.
Related: Experts answer your questions
Trainers Tackle the 8 Most Common Workout Questions
Trainers Tackle the 8 Most Common Workout Questions
1. “How much weight should I use when strength training?”
Think about your rate of perceived exertion — 1 being “chilling on the weight bench” and 10 being “I seriously can’t do one more rep” — to help determine the right weight. Overall, you should be between a 7 and 9 when strength training, with your last set feeling substantially harder than your first. If a given exercise starts to feel easier than that, it’s time to increase weights until you’re back in that range. Tracking each workout and writing down the amount of weight you use is critical to getting stronger. —Tony Gentilcore, CSCS, owner of CORE training studio in Boston
2. “Why are you having me lift weights for fat loss?”
Fat loss requires more than trying to burn as many calories as possible during a workout. In actuality, the body, being the incredible machine that it is, adapts to steady-state activities and begins burning fewer calories during these (typically cardio-heavy) sessions. What’s more, it also becomes more efficient at storing fat. So, if your goal is to effectively change your body composition, you need to incorporate resistance training into your fitness program. Research consistently shows that resistance training is more effective for fat loss compared to steady-state cardiovascular activities. —Tim Hennigan, CPT, online coach with the Trainerize personal training app
3. “Are squats and lunges bad for my knees?”
No, squats and lunges are definitely not bad for your knees. In fact, they are highly beneficial to your entire body, and every joint, provided you are demonstrating excellent technique at all times. In my experience, I have found that the reason people have knee aches and pains is not because they are squatting, but because they are not squatting. A healthy body that is appropriately strengthened from top to bottom will be able to perform and demonstrate a proper squat, deadlift or lunge in any variation. —Holly Perkins, CSCS, founder of Women’s Strength Nation
4. “How many calories will this burn?”
The amount of calories burned during a given workout or single exercise varies greatly. There’s no one simple answer or number to give out. It depends on weight used, intensity, speed, fitness level, muscle mass versus fat mass, caffeine consumption, age, current fitness level…and the list goes on. Focus less on calories burned and more on how hard you’re working. If you cut calories and work out hard, you’re going to see changes. –Mike Donavanik, CSCS, CPT, a California-based trainer
5. “How do I improve my posture?”
Incorporating squats and resistance-band rows into your workout routine will help correct postural imbalances caused by sitting, typing and playing on your phone. Strengthening the glutes with squats is so important because weak glutes allow the pelvis to tilt, which leads to bad posture. Meanwhile, resistance-band rows will help strengthen the muscles that retract your shoulders and counteract slouching. —Taylor Gainor, CSCS, co-founder of LIT Method in Los Angeles
6. “How can I stick with exercise for good?”
The key to long-term success is not to be a lion always fueled by willpower. It’s to be more like Mickey Mouse. Translation: Be fueled by enthusiasm with an occasional turbo boost of willpower. Your mindset on fitness and nutrition can make or break your long-term success. Having an internal dialogue of “I get to” versus “I have to” is one of the key differentiators between people who succeed and fail long-term. It becomes an opportunity when you are fueled by enthusiasm, versus an obligation when you are fueled solely by willpower. You start to live as a fit happy leader with passion and purpose as you raise the bar and defy the odds. —Kyle Brown, CSCS, celebrity trainer
7. “What should I do to strengthen my abs?”
When I answer with “every exercise,” my clients look at me like I have 10 heads. Here’s what you need to know: The core is the musculature that provides support to the rest of our body. You can think of it the same way you think of a trunk supporting the branches on the tree. In order to be sturdy, strong and resilient, you need the trunk to be solid.
So whether you’re performing lunges, squats, deadlifts, pull-ups or push-ups, you’re still engaging your core in order to efficiently move your body and stay balanced. Better yet, the core supports compound movements, which require more than one muscle group (i.e. squats or deadlifts), which means you can go pretty freaking heavy. And the more you progress the intensity of these bigger exercises, the better off your core will be. You may be surprised you’ll get defined abs without any formal “ab work” or crunches. So challenge yourself with total-body movements. —Erica Suter, CSCS, Baltimore-based strength and conditioning coach
8.“How much time should I rest between sets when strength training?”
Most clients want to increase lean body mass and burn fat. Therefore, I tell them that 30 to 90 seconds allows the body to replenish energy stores so they don’t compromise their workout intensity or form, and can therefore trigger the most lean muscle growth. For absolute strength purposes when performing large, barbell exercises, it’s best to rest for two to five minutes. Absolute strength is not a goal for many of my clients, but I do train some clients to increase their one or three-rep maximum barbell deadlift and bench press. When training for muscular endurance — which is more common in endurance athletes — rest periods during weightlifting typically sits around 15 to 30 seconds. —Mark Barroso, CPT, New Jersey-based trainer
As we age, the brain — like any other organ — begins to work less efficiently, so normal signs of decline begin to surface. Our memory might not be quite as sharp as it once was, for example.
Exercising regularly as we get older appears to help defend against some of this decline, both for healthy people who show normal signs of aging and for older people who may be on the path toward developing Alzheimer's disease.
Researchers still aren't sure why this is, or how it happens. Exercise could strengthen some of the pathways our brain uses to relay signals for recent events, or boost the size of certain brain regions that are key for learning and storing memories.
Regardless of the specific mechanism at play in our bodies, the most recent recommendations suggest that working out twice a week may be beneficial in curbing some symptoms of mild cognitive impairment (MCI), a stage that precedes the development of Alzheimer's in some older people. This typically involves more serious problems with memory, language, thinking, and judgment than those that might be displayed by a healthy older person.
RELATED: Fuel up with these snacks
7 R.D.-approved pre-workout snacks you can buy at the supermarket
7 R.D.-approved pre-workout snacks you can buy at the supermarket
KIND Healthy Grains Bars
“At the end of the day, a good pre-workout snack is one that provides carbohydrates, goes down easy, and doesn't leave you running to the bathroom mid-workout. KIND Grain Bars are great carb-rich options that are easy to stash in your handbag. They’re my go-to pre-workout snack when I'm on the run and don't have time to sit down and eat something before I exercise.”
— Edwina Clark, M.S., R.D., C.S.S.D., and head of nutrition and wellness at Yummly
Courtesy of Kind
Fresh fruit and Justin’s Almond Butter packets
“You need to be sure that you’re adequately fueled during your workout. Your pre-workout snack should be comprised mainly of carbohydrates, and a bit of added of protein to keep you satisfied. I like to buy pre-sliced apples and a Justin’s Classic Almond Butter packet, which I’ll grab at the supermarket on my way to spin class.”
“I like to drink chocolate milk before strength training, because it has an easily digestible combination of carbohydrates and protein—two nutrients that your muscles especially need during the healing and repairing process.”
— Caroline West Passerrello, M.S., R.D.N., L.D.N., spokesperson for the Academy of Nutrition and Dietetics
kuarmungadd / Getty Images
Sargento Balanced Breaks Cheese Snacks
“I like these cheese and nut snacks because they're pre-portioned, which helps you avoid eating more than the recommended serving size (which is easy to do with both). The mix of carbs and protein will provide you with sustained energy throughout your workout. I like snacking on this before an afternoon fitness class or an easy run.”
“A 100-calorie pack of Wonderful Pistachio nuts is a great pre-workout snack and it’s available in nearly every drugstore you pass on the way to the gym. With 6 grams of energizing protein and 3 grams of filling fiber (plus good-for-you fats), pistachios will help fill you up without weighing you down during your workout. Plus, their combination of electrolytes and antioxidants will help combat muscle and joint fatigue post-workout as well. They are always what I eat leading up to my 45-minute spin class.”
— Brigitte Zeitlin, R.D., M.P.H., C.D.N., founder of the New York-based BZ Nutrition
Courtesy of Wonderful
Cereal and milk
“I recommend a snack that is easy to digest and contains complex carbohydrates and protein. It’s also important to make sure you’re hydrated, because that’s just as important as the nutrients you’re eating. I like to eat 1 cup of cereal with low-fat milk prior to an intense SoulCycle or kickboxing class, a 30- to 60-minute run, or an intense CrossFit workout.”
Most studies focusing on people with MCI require people to either work out or self-report their own fitness levels. But the latest study measured how fit people were by studying their breathing and heart rate. The researchers then used brain imaging to measure the functionality of peoples' white matter and had them take a series of cognitive tests designed to measure how sharp they were.
Overall, they found that the less fit people were, the weaker their brain's white matter connections, and the worse they did on the cognitive tests.
Two other recent studies of older people with MCI have suggested that merely amping up one's workout routine with the right moves could help slow the brain's decay.
Last May, scientists recruited adults with MCI between the ages of 60-88 and had them walk for 30 minutes four days a week for 12 weeks. The results showed strengthened connectivity in a region of the brain where weakened connections have been linked with memory loss. That development, the researchers noted, "may possibly increase cognitive reserve," but more studies are needed.
Large groups of researchers are taking note of these promising findings. In December, the American Academy of Neurology updated its guidelines to reflect the takeaways of these findings. Based on a series of 6-month studies on aerobic workouts and memory in people with MCI, the new guidelines recommend that people diagnosed with the condition do some form of cardio exercise at least twice a week.
The reason aerobic workouts lift our spirits seems related to their ability to reduce levels of natural stress hormones, such as adrenaline and cortisol, according to a study in the Journal of Physical Therapy Science. Activities like running and swimming also increase overall blood flow and provide our minds fresh energy and oxygen — another factor that could help us feel better.
Aerobic exercise may also have a uniquely powerful positive impact on people with depression. A pilot study in people with severe depression found that just 30 minutes of treadmill walking for 10 consecutive days was "sufficient to produce a clinically relevant and statistically significant reduction in depression."
So whether you're looking for benefits related to mood or memory, the take-home message is clear: the more you move, the healthier you may be.
"It's exciting that exercise may help improve memory at this stage, as it's something most people can do and of course it has overall health benefits," Ronald C. Petersen a fellow of the American Academy of Neurology and the lead author on the most recent guidelines, said in a statement.
While some benefits of exercise can emerge just a few minutes into a sweaty workout, others might take several weeks to crop up. That means that the best type of fitness is any aerobic exercise that you can do regularly and consistently for at least 45 minutes at a time.