A fitness trainer shares the No. 1 exercise for a 'longer life': It has 'major aging benefits'

Starting at age 30, your muscle mass starts to deteriorate. But there are steps you can take to help fend off the negative effects.

As a personal trainer, strength training is the No. 1 type of exercise I recommend to live longer. Research has even shown that people in their 70s with mobility issues can boost their longevity with a strength-training program.

Some major aging benefits include:

• Increased bone health: Regular strength training can help reduce the risk of osteoporosis.
• Muscle maintenance: It allows you to maintain muscle that would otherwise begin to waste away as you get older.
• Better joint mobility: It improves your range of motion and protects your joints by strengthening the muscles that surround them.
• Weight management: Building muscle helps boost your metabolism, making your body more efficient in burning calories.
• Better balance: Improving your balance is critical to helping prevent falls that may lead to injury.

My favorite strength-training routine requires no gym or equipment. I do it every day, and the best part is that it take less than 20 minutes.

What it targets: lower body, core, and knee, hip and ankle joints

Squats help your body perform everyday activities as you age, like getting up from a chair or picking something up off the ground.

How to do a squat:

1. Stand with your feet a little wider than your hips and your toes facing forward.
2. Drive your hips back while bending your knees and pressing your feet firmly into the floor, as though you're about to sit down. Aim to squat parallel, or as comfortably close to floor as you can.
3. Press your heels into the floor to push up and return to a standing position.
4. Do 12 to 15 reps.

What it targets: hamstrings, quadriceps, glutes and calves

As a unilateral movement (working one side of the body at a time), lunges improve your stability and help correct muscle imbalances by strengthening each side of your body separately.

How to do a static lunge:

1. Stand with your feet hip-width apart and take one giant step forward into a split stance.
2. Keep your back heel off the ground as you lower your body, until your knees form 90-degree angles.
3. Plant your front foot and the ball of your back foot into the mat, and straighten back into a standing position.
4. Do 10 to 12 reps on each side.

What it targets: glutes, hamstrings, lower back and muscles that support the spine

Hip bridges (also called glute bridges) can open the hips and increase flexibility, improving mobility and helping to prevent lower back pain or injury.

How to do a hip bridge:

1. Lay on your back with your knees bent. Plant your feet firmly on the mat and place your arms alongside your body flat on the floor, palms down.
2. Inhale as you push your heels into the mat and raise your hips toward the ceiling.
3. Squeeze your glutes at the top.
4. Exhale while you lower your hips back down to the floor.
5. Do 12 to 15 reps.

What it targets: core

Planks help to strengthen your core, enhancing overall functional strength. It improves your balance and tones the shoulders and glutes.

How to do a plank:

1. Start with your forearms and toes on the floor and your face looking down at the floor. Keep your elbows under your shoulders and your forearms facing forward.
2. Engage your abdominals by pulling them in toward your spine, while keeping your torso and hips level and parallel to the floor.
3. Hold for 10 to 30 seconds.

What it targets: shoulders, chest, triceps and core

Push-ups increase upper body strength. They help improve your endurance and stability so you can be steadier on your feet as you age.

How to do a push-up:

1. Start in a high plank position with your toes on the ground and your hands on the floor, arms spread slightly wider than your shoulders. Keep your arms straight and hold your body up.
2. Inhale and slowly bend your elbows, lowering your body toward the floor as you keep your core tight.
3. Exhale while contracting your chest muscles to push back up through your palms, returning to your starting position.
4. Do three to 10 reps.

Modified bent-knee push-up

1. Instead of starting in the high plank position, hold your arms straight but place your knees on the floor, keeping your body on an incline.
2. Bend your elbows to lower toward the floor, then push your upper body back to the start position.
3. Do three to 10 reps.

Patricia Greaves is a certified fitness trainer, corrective exercise specialist and nutrition coach. She's the founder of StrongHer Personal Training, which seeks to improve overall wellness for women over 40. She is part of the Strength in Diversity Initiative, a writer for HealthDay, a wife and a mom to three daughters. Follow her on Instagram and LinkedIn. 

Don't miss:

• A fitness trainer shares the 5 exercises she does every day to ‘look and feel younger’
• Can you pass this ’10-second balance’ test? Here’s why it’s the secret to a longer life, say health experts
• A fitness trainer shares what she does every morning to prevent neck and shoulder pain

Want to be smarter and more successful with your money, work & life? Sign up for our new newsletter here!

Take your business to the next level: Register for CNBC's free Small Business Playbook virtual event on August 2 at 1 p.m. ET to learn from premier experts and entrepreneurs how you can beat inflation, hire top talent and get access to capital.