Morning Exercise, Weight Training, and Cardiovascular Safety: A Review of the Evidence

Prepared by Luke Rowe, NASM-CES | FlexFlow Personal Training

I had a client ask me about if there is any sort of risk to exercising in the morning.

Objective

To clarify whether exercising in the morning poses risks to hormonal balance, bone density, and cardiovascular health particularly in adults aged 60 and above. This report reviews cardiovascular health particularly in adults aged 60 and above. This report reviews peer-reviewed studies and clinical trials relevant to blood pressure, heart attack risk, hormone response, bone integrity, and metabolic health.

Key Findings

1. Morning Exercise Is Associated with Reduced Cardiovascular Risk

Several large-scale studies have found that morning activity is linked with lower incidence of heart disease and stroke.

A 2022 study of 86,657 participants (mean age: 62) using accelerometer data found that physical activity between 8:00 AM and 11:00 AM was associated with 11–16% lower risk of coronary artery disease and 17% lower risk of stroke compared to midday exercisers.

• Source: Wang et al., European Journal of Preventive Cardiology (2022)

• Summary: European Journal – Study on Morning Exercise and Cardiovascular Risk

*This study adjusted for factors including sleep, BMI, alcohol intake, and medication use.

• Supporting articles:

• IDEA Health & Fitness Article

• Observatoire Prevention Summary

2. No Increased Risk of Heart Attack During Morning Sessions

Despite natural circadian peaks in blood pressure and clotting factors, morning exercise has not been shown to increase adverse cardiovascular events in healthy individuals.

A 2006 review of cardiac rehabilitation patients found no difference in safety between morning and afternoon exercise.

• Source: Cornelissen et al., Clinical Cardiology (2006)

• PubMed Summary: https://pubmed.ncbi.nlm.nih.gov/16737342/

Population studies using wearable devices (e.g., UK Biobank) confirm cardiovascular benefits not risks linked to morning training.

Independent reviews reach the same conclusion.

• Article: News-Medical Summary

3. Morning Activity Improves Blood Pressure and Glucose Control

A 2019 randomized controlled trial showed that morning workouts led to significant reductions in systolic blood pressure, especially when movement breaks were included.

• Source: Wheeler et al., Hypertension (2019)

• AHA Journal: https://www.ahajournals.org/doi/10.1161/HYPERTENSIONAHA.118.12373

A 2022 study found that morning exercisers experienced greater reductions in abdominal fat and blood pressure compared to evening exercisers.

• Source: Kang et al., Frontiers in Physiology (2022)

• Study: https://www.frontiersin.org/articles/10.3389/fphys.2022.893783/full

4. Cortisol Peaks Are Natural and Not Harmful

Cortisol, often cited as a concern for morning training, naturally spikes in the early morning. This is not harmful in fact, morning workouts can help regulate stress hormones.

Meta-analyses show that regular exercise reduces baseline cortisol, particularly in older adults.

• PubMed Summary: https://pubmed.ncbi.nlm.nih.gov/35777076/

• Moderate early workouts help balance the hypothalamic-pituitary-adrenal (HPA) axis.

• Source: Hayes et al., Sports Medicine Review (2010)

• Study: https://doi.org/10.2165/11536800-000000000-00000

Further reading:

• Stanford Lifestyle Medicine – Exercise and Cortisol

• MIDUS Study – Cortisol & Aging

5. Resistance Training and Bone Density in Older Adults

Resistance training is a proven intervention to reduce bone loss and improve bone mineral density (BMD).

High-intensity resistance training significantly increased BMD in postmenopausal women.

• Source: Watson et al., Journal of Bone and Mineral Research (2015)

• Study: https://doi.org/10.1002/jbmr.2351

• A meta-analysis confirmed strength training prevents or slows bone loss in adults over 60.

Source: Zhao et al., Osteoporosis International (2015)

• Meta-Analysis: https://doi.org/10.1007/s00198-015-3034-0

• ACSM recommends resistance training at least 2x/week to reduce fracture risk.

• ACSM Position Stand: https://doi.org/10.1249/MSS.0b013e3181a0c95c

6. Metabolic and Functional Benefits of Strength Training

Weight training supports metabolic health and physical independence.

Resistance training improves insulin sensitivity, glucose uptake, and resting metabolic rate.

• Ibanez et al., 2005 – Diabetes Care

• https://doi.org/10.2337/diacare.28.3.662

• Holten et al., 2004 – Journal of Applied Physiology

• https://doi.org/10.1152/japplphysiol.00316.2003

Strength training counteracts sarcopenia (age-related muscle loss), supporting mobility

and balance.

• Peterson et al., 2011 – Medicine & Science in Sports & Exercise

• https://doi.org/10.1249/MSS.0b013e3181eb6265

Muscle is metabolically active tissue essential for energy regulation and healthy aging.

Addendum: Clarifying the Research on Morning Exercise and Resistance Training in Older Adults

Recent conversations around morning workouts and strength training have raised questions

about safety and effectiveness, particularly in older populations. While concerns about circadian

rhythm disruption, heart attack risk, or general safety are understandable, extensive research

supports that morning movement and resistance training are not only safe but beneficial,

when properly prescribed. This holds true for both men and women, with some physiological

differences worth noting.

1. Morning Exercise Enhances Circadian Health, Not Disrupts It

Cortisol Peaks Are Natural: Cortisol, the body’s natural “get up and go” hormone, is

designed to peak in the morning. Exercising during this window helps reinforce healthy

circadian rhythms, particularly important for aging adults whose rhythms tend to weaken

with age.

Women May See Slightly Greater Sleep Benefits: Morning exercise has been shown

to improve sleep onset and quality for both sexes, but some studies suggest women

experience slightly greater improvements in deep sleep following early workouts.

Blood Pressure & Fat Reduction: A 2022 study found morning exercise led to greater

abdominal fat reduction and systolic blood pressure drops, especially in women

compared to men (Kang et al., Frontiers in Physiology).

2. No Elevated Risk of Heart Attack from Morning Workouts

Large-Scale Studies Confirm Safety: A 2022 study of 86,657 adults (mean age: 62)

found that exercising between 8:00–11:00 AM was associated with a significantly lower

risk of coronary disease and stroke, in both men and women (Wang et al., European

Journal of Preventive Cardiology).

Sex-Specific Heart Trends: While men generally experience higher baseline

cardiovascular risk, no evidence shows that morning exercise elevates that risk in

either gender when the activity is monitored and adapted to fitness level.

Clinical Trials in Older Adults: In rehab and aging populations, morning sessions did

not show increased adverse cardiac events, including in those with prior heart disease

(Cornelissen et al., Clinical Cardiology).

3. Resistance Training Benefits Both Men and Women are Unique and

Powerful Bone Health: Postmenopausal women are at higher risk for osteoporosis due to

hormonal changes. Studies show high-intensity resistance training improves bone

mineral density significantly in women (Watson et al., 2015). Men also benefit,

particularly in reducing fracture risk and maintaining skeletal strength with age.

Muscle & Metabolism: Men typically lose muscle at a faster absolute rate due to larger

baseline muscle mass, while women may experience a greater relative loss

post-menopause. Strength training in both groups:

○ Preserves lean tissue

○ Improves balance and coordination

○ Enhances insulin sensitivity and blood sugar control

Functional Outcomes: Both men and women experience enhanced independence,

mobility, and fall prevention with resistance training, even in their 70s and 80s.

Final Considerations

Of course, all training programs should be tailored to the individual’s medical history,

medications, and mobility. But resistance training, when done correctly, is not only safe for older

adults, it is essential. It’s not about lifting heavy at all costs; it’s about preserving quality of life,

independence, and function.

Being overly cautious in the face of decades of validated science is not protective, it’s limiting.

While the science is clear, every individual has unique needs. Factors like medications, chronic

illness, sleep, stress, and nutrition should all be considered when designing a program.

Conclusion: Morning workouts and resistance training are safe, beneficial, and effective for

aging adults when personalized and properly supervised.

Prepared by:

Luke Rowe, NASM-CES

FlexFlow Personal Training | Corrective Exercise Specialist

www.flexflowbylukerowe.com