Your body is constantly evolving, and so should your fitness routine.

In your teens, 20s and 30s, the only workout you may have needed to maintain a slender, shapely physique was an occasional jog and a few bicep curls. Then you entered your 40s and something strange happened — your workouts stopped working. Your buns now resemble toast and you have to work twice as hard to see results.

Does that sound familiar?

At any age, the goal is to look healthy and lean. However, you must adjust your workout routines to fit the physiological changes that naturally occur as you age. Here are the top toning tweaks to make in your 40s, 50s, 60s, 70s and beyond.

The 40s

Your spare time likely isn't abundant at an age when much of it is dedicated to shaping your career and family rather than your body. So you have to wedge in workouts wherever possible.

If your job doesn't require a long commute, consider biking or walking to work. Cardiovascular exercise is necessary for heart health, disease prevention, and weight maintenance. Small solutions such as taking the steps rather than the elevator or practicing bodyweight exercises at your desk such as push-ups, planks and squats, will make an impact.

For the days you have more time for exercise, rotate between stress-reducing and flexibility-promoting exercises, such as yoga or Pilates, and heart-elevating, high-intensity exercises such as spinning, boxing or a strength training class. Always remember to warm up before and cool down afterward.

The 50s

If you haven't been physically active before, now is the time to amp up aerobic and weight training to reverse or lessen the effects of such chronic conditions as high cholesterol, elevated blood pressure, diabetes and heart disease.

For women, this decade often means declines in estrogen, one of the hormones responsible for metabolizing calories consumed and retaining bone mass and density. Weight gain around the mid-region is a frequent side effect, as well as osteoporosis. Women in their 50s should focus on weight-bearing exercises, such as walking and weight training, to strengthen the bones and crush calories.

The 60s

As kids leave home, and careers may become less demanding, many 60-somethings find they have more time to concentrate on overall health and well-being. Here are some top ways to put that time to good use:

  • Fuse fitness into your life by scheduling daily walks. Also consider biking or swimming.
  • Mix machines and free weights when exercising. Machines are ideal for those looking for structural support, while free weights are effective in encouraging core strength, balance and stability.
  • Buff up your body and your brain by trying new-to-you workouts such as Kettlebells, boxing or Zumba. Movements that require concentration and memorization are excellent for preserving cognitive skills.
  • Eat well. If you're retired, you may have more time to indulge in sugary snacks and sips. A well-balanced diet will aid in digestion, blood glucose regulation, and warding off weight gain.

70s and up

The key takeaway for this period in your life is remembering the connection between fitness and freedom. Having an able mind and body keeps you independent and self-sufficient.

Ashley Greenblatt demonstrates a beginner exercise for balance.
Courtesy of Ashley Greenblatt
Ashley Greenblatt demonstrates a beginner exercise for balance.
  • Listen to your body's cues. If arthritic joints are stiff and achy, stick with low-impact activities such as walking, swimming, cycling and yoga.
  • Include balance training to keep your joints strong and prevent debilitating falls. Add this beginner balance exercise to your routine: Stand on one foot for 45 to 60 seconds. Repeat three times, then switch legs.
  • Practice functional fitness. Exercises such as chair squats, lunges and abdominal twists mimic the motions of your everyday life.

Ashley B. Greenblatt is a certified personal trainer and wellness coach. To learn more, visit ashleyblakefitness.com.