As we age, things slip our mind.

We misplace keys and phones and glasses (often), can’t recall why we entered a room, and forget the names of actors, favorite vacation spots and sometimes, briefly, a family member or grandchild.

Well, here’s some good news, along with the fact that dementia and Alzheimer's rates are actually down quite a bit. This memory aid can make it easy to recall the amount of exercise you should get as a senior: 150-2-2.

That means you should get 30 minutes of aerobic exercise five days a week for 150 minutes a week total, plus exercise that strengthens muscles, and improves balance and flexibility, two days a week. That's the recommendation from the Centers for Disease Control and Prevention, which offers a lot of good information on its Older Adult Activity Overview page.

Preeti Gupta, a family practice physician with Bayhealth Medical Group in Milford, said those recommendations offer good guidance, but they should be tailored to each individual.

"The CDC recommendation is a strong, evidence-based target for older adults, but the most important message is that some activity is much better than none, and the program should be adapted to the person’s baseline function, medical conditions and fall risk,” she said.

And she noted that fitness as we age "isn't primarily about athletic performance" and should be part of a regular plan.

"It is about preserving independence and quality of life," she said. “Move more, sit less, walk regularly, strengthen your muscles at least twice a week, and keep practicing your balance. Consistency is more important than exercising intensely.”

Britt Hammond, a personal trainer and the founder of Britt Marie Fitness in Lewes, said the appropriate amount of exercise not only helps you stay healthy, but also improves your mood and cognitive function. Done properly, it can also alleviate pain that comes with aging.

Sloth saps strength

Gupta said all three types of basic fitness exercise are critical, but seniors sometimes underestimate the importance of building and retaining muscle.

"Lower-body and core strength are critical for getting out of a chair, climbing stairs, carrying groceries, recovering from a stumble and remaining independent," she said.

Hammond recommends starting slow, with the weight load or band resistance at a reasonable level. For any type of exercise, it's important to work up gradually.

“Listen to your body. You know the right level better than anyone else," she said. "I think some people overdo it and get discouraged because they don't meet their goals right away, so ease into any plan to set yourself up for success.”

Balance and flexibility are vital

Balance and flexibility can be achieved in a number of ways, including through yoga, tai chi, Pilates or a simple set of stretches and balance exercises you can find online. Three easy ones involve standing on one foot for 10 seconds with a chair to support you, walking alongside a countertop toe-to-heel for 20 steps or sitting on a sturdy chair and getting up without using your arms, then sitting back down slowly 10 times.

Ellen Spell, owner of Sea Barre Fitness in Millsboro, Lewes and Bethany, said balance is often affected by diminishing strength. Her studios offer a wide range of classes aimed at improving both.

"Your whole body plays a role in balance. Core strength is very important, of course, but even if you have weak ankles, it can affect your balance,” she said. "You want to avoid falls, and be able to reach down and pick something up or reach something higher without injuring yourself.”

Exercise can also be therapeutic, she said: “Our back, for instance,  can get very stiff and tight, and it feels good to loosen it up. The right exercises feel like a massage.”

Try practical aerobic options 

The CDC recommends moderate workouts such as brisk walking. It says on a 1-10 scale, if exhausting exercise is 10 (working out as hard as you can) and sitting and watching "Seinfeld" reruns is 1, moderate is about 5.

Its website gives this guidance: "It will make you breathe harder and your heart beat faster. You'll also notice that you'll be able to talk, but not sing the words to your favorite song.”

Walking, biking and swimming are recommended, but the CDC notes that aerobic exercise can also be functional, like walking to the store, mowing the lawn or cleaning out the garage.

Gupta offers two other important tips:

Start slow and progress gradually. ”Someone who has been sedentary should not suddenly try to complete 150 minutes of aerobic plus a full strength program. Even five- to 10-minute periods of walking and simple resistance exercises are useful starting points.”

Prioritize function and safety rather than intensity. ”Proper footwear, hydration, safe surroundings and appropriate support for balance exercises matter. People with significant heart or lung disease, recurrent falls, severe joint problems, or symptoms such as exertional chest pain, unusual shortness of breath, dizziness or fainting should have those issues evaluated before substantially increasing exercise.”