Strength After 40: What the Research Actually Says
Kate Somrak, Founder
Published
Last updated
At 25, I went to the gym to burn off what I ate the night before. At 41, I'm walking into the gym wondering if I've eaten enough protein to actually build something while I'm there.
That is a WILD change in perspective.
I want to be able to ski when I'm 70 years old, I don't care what number the scale is showing me today.
I don't want a smaller life so I can maintain a smaller body.
Muscle mass declines gradually with age. A large analysis of U.S. adults put the drop for women at roughly 4.5 to 5 percent per decade. The research keeps pointing to the same two things that help: using your muscles, especially with resistance training, and eating enough protein.
What actually changes
The same analysis found that muscle mass peaks in early adulthood and then decreases progressively, decade by decade. Researchers call the age-related loss of muscle mass, strength and function sarcopenia.
It's never one thing. A widely cited review describes it as having many contributing causes, including inactivity, changes in hormones and changes in nutrition. That's actually encouraging, because some of those are things you can work with.
What the research says helps
Moving, and lifting. The same review highlights both resistance training and aerobic exercise for supporting muscle growth and function as you age. You don't need a perfect program. You need one you'll come back to.
Enough protein. The standard recommendation for adults is 0.8 grams of protein per kilogram of body weight per day. An international expert group, PROT-AGE, recommends at least 1.0 to 1.2 grams per kilogram for people over 65. That works out to roughly 0.45 to 0.55 grams per pound.
Those higher numbers were set for people over 65. Nobody has settled the right number for your 40s and 50s yet, and it's worth talking through with your doctor or a dietitian, especially if you have a health condition.
Why strength means something different now
Strength isn't about proving how much you can carry. It's about creating a life that supports the woman who's carrying it.
Strength shouldn't have to feel heavy.
Where KESSARA fits
Some mornings I go down to our home gym. Other mornings I stay in bed. KESSARA isn't a workout and it isn't a meal. It's 4 grams of essential amino acids, plus magnesium and electrolytes, that I can take every day either way.
I take The Daily Ritual first thing in the morning so that no matter what happens that day I know I've taken a moment out of my day to support myself. For nobody else. Just me.
If you want to be here from the beginning, join the Founding Circle.
Sources
- DXA-based detection of low muscle mass using the Total Body Muscularity Assessment Index (TB-MAXI): a new index with cutoff values from the NHANES 1999–2004. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8837094/
- Volpi E, Nazemi R, Fujita S. Muscle tissue changes with aging. Current Opinion in Clinical Nutrition and Metabolic Care. 2004;7(4):405-410. https://researchexperts.utmb.edu/en/publications/muscle-tissue-changes-with-aging/
- Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. Journal of the American Medical Directors Association. 2013;14(8):542-559. https://doi.org/10.1016/j.jamda.2013.05.021