Why Certain Exercise Intensities Work for You (and Others May Not)

If you have experienced results from exercise that are nothing like you want, this episode intends to help explain why certain exercise intensities work for you right now and others that have previously may not.

What I want to make clear is… you want intensity and effort level matters for success long term. But short term sometimes you have to pivot.

Certain workouts that once gave results may suddenly stop working during midlife. 

Let’s dive into the connection between cortisol, exercise intensity, recovery, hormones, blood sugar, and stress—and why walking, recovery, and smarter training may actually deliver better results than constantly pushing harder.

This conversation is packed with empowering reminders that fitness after 50 should support your energy, metabolism, sleep, and quality of life—not drain them. 

By the end of this episode, you’ll better understand how you can work with your body instead of against them, especially knowing the exercise intensities that work for you.

Exercise Results Change in Midlife

• Intensity still matters—but timing and recovery matter too
• Know when the body needs a temporary pivot

Stress, Cortisol, and Exercise Intensity

• Cortisol acts as both a stress hormone and energy hormone.
• High-intensity exercise can stimulate lean muscle and fat burning.
• There is a difference between productive exercise stress and chronic life stress.
• Exercise at greater than 75% VO2max causes energy demands to surpass the rate at which aerobic pathways can efficiently supply at ATP. Cortisol is released as part of the body’s acute stress response to mobilize glucose and stimulate glycogenolysis (breakdown stored glycogen into usable sugar) to fuel muscles.

Coffee, Blood Sugar, and Midlife Weight Gain

• Elevated cortisol can increase blood sugar
• Even black coffee may contribute to stress responses in some women
• Stress eating and blood sugar spikes influence belly fat
• Blood sugar regulation becomes more important during midlife

   

When Exercise Intensities Work for You and When They Backfire

Why Everyone Keeps Saying “Go for a Walk”

• There is a science-backed benefits of walking for stress reduction
• Low-intensity walking lowers cortisol instead of increasing it – effective without overstressing the body.
• Walking supports blood sugar balance and recovery

When Walking Becomes Too Much

• Excessive power walking or long-duration walking can backfire
• There are risks of combining high intensity with long duration walks
• There are VO2 max and exercise thresholds
• The body moves from aerobic to anaerobic stress

Low-Intensity Exercise Can Lower Cortisol

• Enjoyable walks reduce stress hormones.
• Moderate movement helps the body use circulating cortisol.
• Avoiding “punishing” workouts during stressful seasons
• Recovery matters more than pushing harder

HIIT, Recovery, and Fat Burning

• Short sprint intervals for VO2 max and visceral fat reduction are beneficial.
• Too much HIIT without recovery elevates cortisol.
• It’s dangerous to combine intense exercise with low-carb dieting
• Insufficient recovery signals the body to store fat

Recovery Needs Change During Midlife

• Recovery becomes more important after hormonal shifts.
• Sleep, carbohydrates, calories, and exercise timing impact cortisol.
• Fitness routines need adjustment during menopause.

Signs You’re in a Cortisol Challenge

• Poor sleep and digestion changes
• Irritability, low focus, and fatigue
• Increased sickness or injury frequency
• Feeling exhausted after exercise is a warning sign

When HIIT Stops Working

• “Critical mass” stress overload
• Even healthy stressors can backfire
• The body reacts when stress buckets overflow

How do you know you’re not going to benefit from HIIT/SIT?

• Trial and error: you don’t feel good after 
• Frequently tired/exhausted even though exercising 
• Haven’t yet established lower pyramid items (walking/movement/weights) 
• Haven’t got a stable energy/fairly optimal sleep pattern established

   

Exercise Intensities Work for You When Your Body Feels Safe and Recovered

Signs You’re Not Recovering Well

• sleep is worse or not improving even with exercise 
• Waking resting heart rate is 5 or more beats higher than usual 
• Constantly on-edge
• You could take a nap after exercise (of any kind) 

The Hidden Risks of the “Middle Zone”

• Moderate intensity done too often may increase cortisol
• Endurance exercise may become problematic in midlife
• Endurance workouts as occasional “soul food”

Resetting Before Burnout

• Temporary low-intensity phases can restore recovery
• Listening to the body’s signals is important
• “Go harder or go home” no longer works
• Shifting toward supportive, sustainable exercise

Emotional Attachment to Certain Workouts

• Some women struggle to give up endurance exercise
• Meet other women where they are
• Balance emotional needs with physical recovery

   

What We’ll Try:

When times are tough, life stressors are HIGH…. 
SHIFT from your normal routine: 

• Lower intensity exercise may help you maintain your energy for what’s needed 
• HIIT might work for you in small doses (20 minutes start to end) 
• Test which of those two might be best for you. Lean into the one your gut is telling you. If it isn’t working, try the other. 
• Do stay consistent with resistance training (10 minutes of compound exercises is better than nothing)