Why Dr. Stacy Sims Says Women Over 35 Need Less “Medium” Exercise and More Strength Training

For years, many women believed the formula for staying fit was simple:

More cardio. More sweat. More calories burned.

Spin classes, long runs, boot camps, and high-energy group fitness classes became the go-to solution for fat loss and health.

However, exercise physiologist and women’s health researcher Dr. Stacy Sims has been challenging that approach for years.

Her message is not that cardio is bad.

Instead, she argues that many women over 35 spend too much time doing what she calls “gray zone training” and not enough time building muscle and performing true high-intensity work.

At ELITE Fitness Alliance, we see this all the time.

Women come to us exercising five or six days a week but still struggle with:

Fat loss
Energy levels
Recovery
Muscle loss
Strength
Stubborn body composition changes

The issue often is not a lack of effort.

It is doing the wrong type of exercise for this stage of life.

What Dr. Stacy Sims Means by “Gray Zone Training”

According to Dr. Sims, many popular workouts keep people in a moderately hard effort level.

Examples may include:

Long spin classes
Extended boot camps
Endless circuits
Daily OrangeTheory sessions
Constant calorie-burning workouts

These workouts are not necessarily harmful.

The problem is when they become the majority of your training.

You are working hard enough to create fatigue, but often not hard enough to produce the powerful adaptations that come from true high-intensity intervals or progressive strength training.

Dr. Sims often summarizes this concept with:

“Women need to lift heavy and sprint.”

Why Things Change After 35

As women enter perimenopause and menopause, hormonal changes begin to affect:

Recovery
Muscle protein synthesis
Bone density
Body composition
Stress response

Research published in Sports Medicine and recommendations from the North American Menopause Society show that maintaining muscle mass becomes increasingly important during midlife.

Without resistance training, women naturally lose lean muscle as they age.

Less muscle can contribute to:

Reduced metabolism
Lower strength
Increased injury risk
Declining bone density

This is one reason why the scale becomes less important and strength becomes more important.

What True High-Intensity Training Actually Means

Many people think every sweaty workout is HIIT.

In reality, true high-intensity interval training involves:

Short work periods
Near maximal effort
Full recovery between intervals

Examples include:

20-second bike sprints
Rowing intervals
Hill sprints
Assault bike efforts
Power-based kettlebell intervals

The goal is quality, not exhaustion.

Research consistently shows that properly programmed HIIT can improve:

Cardiovascular fitness
Insulin sensitivity
VO2 max
Metabolic health

And it can do so in far less time than traditional cardio.

Strength Training Is the Foundation

Dr. Sims repeatedly emphasizes that women over 35 should prioritize strength training.

Strength training helps:

Preserve muscle mass
Support metabolism
Improve bone density
Reduce injury risk
Increase confidence
Support healthy aging

Research from the American College of Sports Medicine and the National Institute on Aging consistently supports resistance training as one of the most powerful tools for healthy aging.

For many women, two to four strength sessions per week provide tremendous benefits.

Cardio Is Still Important

This is not a message to avoid cardio.

Cardiovascular training remains important for:

Heart health
Endurance
Recovery
Longevity

The goal is balance.

Instead of doing moderate-intensity cardio every day, many women benefit from combining:

Strength Training

2 to 4 sessions weekly

True High-Intensity Intervals

1 to 2 sessions weekly

Zone 2 Cardio

Walking, cycling, hiking, or steady-state exercise

Recovery and Mobility

Stretching, mobility work, and adequate rest

How ELITE Fitness Alliance Applies These Principles

Many of the concepts Dr. Sims discusses are already built into our programs.

Strength Training Sessions

Our classes focus on progressive resistance training to help clients maintain muscle and support bone health.

Core and Cardio Fusion

These sessions combine conditioning with functional movement and stability.

Kettlebell Classes

Kettlebells provide power, strength, and cardiovascular benefits simultaneously.

Mobility and Recovery Training

Because recovery becomes increasingly important after 40.

Our goal is not to leave clients exhausted.

Our goal is to leave them stronger.

The Bottom Line

Dr. Stacy Sims is not saying spin classes or OrangeTheory are bad.

She is saying that women over 35 may need a different balance of training.

Instead of chasing calories burned, focus on:

✔ Building muscle
✔ Preserving bone density
✔ Performing true high-intensity intervals
✔ Recovering well
✔ Training for longevity

Because after 35, the goal is not simply to do more.

The goal is to do what works best for your body.

References

Stacy Sims, PhD. Next Level.
Sims ST, Heather AK. “Myths and Methodologies: Redefining Exercise for Women.” Women in Sport and Physical Activity Journal.
American College of Sports Medicine Position Stand on Resistance Training.
North American Menopause Society Guidelines.
National Institute on Aging. Exercise and Physical Activity for Healthy Aging.

The Goal Isn’t to Burn More Calories

The goal is to have the strength and energy to enjoy life.

To travel.

To play with your children or grandchildren.

To feel confident in your body.

To stay independent for decades to come.

At ELITE Fitness Alliance, we’re passionate about helping people train for the life they want to live, not just the number they want to see on the scale.

Ready to become stronger for life?

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Or contact us to learn how our personal training and small group coaching programs can help you stay strong for life.

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