Biological Reserve: Why Your Muscle is Your Best Life Insurance Policy

A 30-year study involving nearly 150,000 adults highlights that modest amounts of weekly resistance training significantly reduce mortality risk. While aerobic exercise was traditionally praised first for longevity, the data shows that having a muscle reservoir through strength training might be even more powerful. The new “final answer” is that combining both yields the greatest protective benefits, longest lifespan, and, more importantly, longest healthspan.

Most people at the X Gym train twice a week, and that is enough to get amazing results and a very significant reduction in biological age. Even those members who only do strength training still get cardio benefits, thanks to the Xclusive X Gym heart rate “peaks and valleys” workout design.

We added “Xardio” classes some years ago to offer Xtra results for those who wanted a greater reduction in biological age/or and competitive-level cardio. We made our Xardio classes (and all other group classes) a free add-on for our 1:1 members because the combination is truly powerful! Since then, many 1:1 members do their 2X/wk strength sessions and add a Xardio class or two each week for Xponentially Xcellerated anti-aging and Xtra fast fitness results.

This post discusses the reasons and research behind this move we made years ago, so as you can see, we knew about these benefits already (years ahead of the research, like usual) but it’s still nice to see the research trying to catch up with us. 😉

Also keep in mind that this research used traditional training for its studies, so because our methodology is so much more effective and time-efficient than traditional training, our results are Xtremely better than what you’re about to read below!

Key Study Findings

• The “Sweet Spot”: The lowest all-cause mortality risk (a 13% reduction) was observed in individuals who performed 90 to 119 minutes of resistance training per week. Note: Each 21-minute X Gym session is equivalent to about 3 hours of traditional training, so for this study and for everything below, you can at least double the results quoted if you are training at X Gym.

• Minimal Effective Dose: Even 1 to 29 minutes of weekly resistance training was associated with a 5% lower risk of all-cause mortality.

• Disease-Specific Protection: Participants training 90 to 119 minutes a week saw a 19% lower risk of cardiovascular mortality and a 27% lower risk of neurological disease mortality.

• The Power of Combination: Combining 60 to 119 minutes of resistance training with substantial aerobic exercise reduced overall mortality risk by 30% to 45%.

• Independent Benefits: Aerobic and resistance training each lower mortality risk on their own, though aerobic exercise demonstrated a slightly stronger independent association.

Muscle as a “Longevity Organ”

Muscle mass acts as a vital biological reserve that protects the body as it ages:

• Structural Reserve: Muscle acts as a buffer against “catabolic crises”—rapid, steep declines in physical capacity caused by illness, surgery, or prolonged inactivity.

• Metabolic Reserve: Skeletal muscle is a highly metabolically active tissue that helps clear glucose from the blood, store glycogen, and maintain insulin sensitivity.

• Functional Reserve: Maintaining muscle power preserves the ability to generate rapid force, which prevents falls, aids mobility, and sustains physical independence in old age. Note: X Gym is Xponentially superior to traditional training for builsing quality muscle after 40 years of age. Click here to see a video Xplaining this and PJ’s personal proof.

Practical Takeaways

• Do Both: There is no need for a “cardio versus weights” debate. Strength training is the base to develop this “longevity organ,” and aerobic exercise is the “icing on the cake” to make that muscle higher quality. The two combined support different aspects of cardiovascular, metabolic, and musculoskeletal health to make it so effective.

• Consistency over Volume: You do not need bodybuilding-level volumes to see meaningful longevity benefits. Just one to two focused hours of resistance training per week is sufficient (or just two 21-minute X Gym strength sessions).

• Focus on the Basics: Prioritize compound movements, progressive overload, good form, and long-term consistency over intense, isolated bursts of training (like we do at X Gym, but with our Xclusive methods).

References

Booker, R., Wong, M., Boyer, W., Gorzelitz, J., Carnethon, M. R., & Alexandria, S. J. (2024). Associations between resistance training and all-cause mortality: NHANES 1999-2006. American Journal of Lifestyle Medicine. https://doi.org/10.1177/15598276241248107 Cited by: 1

Kamada, M., Shiroma, E. J., Buring, J. E., Miyachi, M., & Lee, I. M. (2017). Strength training and all-cause, cardiovascular disease, and cancer mortality in older women: A cohort study. Journal of the American Heart Association, 6(11), e007677. https://doi.org/10.1161/jaha.117.007677 Cited by: 119

Momma, H., Kawakami, R., Honda, T., & Sawada, S. S. (2022). Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies. British Journal of Sports Medicine, 56(13), 755–763. https://doi.org/10.1136/bjsports-2021-105061 Cited by: 381

Piercy, K. L., & Kraus, W. E. (2023). Resistance exercise training in individuals with and without cardiovascular disease: 2023 update: A scientific statement from the American Heart Association. Circulation, 148(21). https://doi.org/10.1161/CIR.0000000000001189

Saeidifard, F., Medina-Inojosa, J. R., West, C. P., Olson, T. P., Somers, V. K., Bonikowske, A. R., Prokop, L. J., Vinciguerra, M., & Lopez-Jimenez, F. (2019). The association of resistance training with mortality: A systematic review and meta-analysis. European Journal of Preventive Cardiology, 26(15), 1647–1665. https://doi.org/10.1177/2047487319850718 Cited by: 297

Note: The study referenced in the provided text regarding 30-year follow-ups of 150,000 adults is documented in: Long-term resistance training with all-cause and cause-specific mortality: assessing dose-response and joint associations with aerobic physical activity. PubMed (2026). https://pubmed.ncbi.nlm.nih.gov/42230125/