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Recent exercise conference presentations cover cardio-respiratory fitness

Exercise and Health Recent Conference Presentations

Recent exercise conference presentations cover cardio-respiratory fitness for longevity, metabolic flexibility for aging, and the benefits of creatine supplementation.

Scientifically reviewed by: Gary Gonzalez, MD, in November 2024. Written by: Ben Best.

Exercise is a frequent topic at health and longevity summits.

This report focuses on highlights from recent conference presentations that suggest optimal ways of benefiting from exercise.

Cardiorespiratory Fitness for Longevity

Rhonda Patrick, PhD (host of the FoundMyFitness podcast) is passionate about cardiorespiratory fitness for health and longevity. She has cited the fact that aerobic exercise, whether walking, running, or cycling, reduces both systolic (heart pumping) and diastolic (heart relaxing) blood pressure.1

A meta-analysis of studies found that longer intervals of exercise will invariably increase cardiovascular fitness (measured by VO2 max, the maximum volume of oxygen used by the body during intense exercise).2 A recent study in men found that high-intensity interval training (short bursts of high-intensity full-body movements followed by short rest periods) increases VO2 max more than sprint interval training (short bursts at maximal intensity followed by longer periods of rest). However, a review of 19 studies showed that both forms of exercise produce similar gains for cardio-vascular fitness.3,4

One study found that six minutes of high-intensity cycling intervals increased circulating brain-derived neurotropic factor, important for learning and memory, four to five times more than prolonged, low-intensity cycling.5

A study of middle-aged men, followed for 46 years, showed that VO2 max was a significant predictor of cardiovascular mortality and all-cause mortality. Those in the highest 5% lived about five years longer than those in the lowest 5%.6 This and other evidence suggest that VO2 max is a greater predictor of cardiovascular mortality and all-cause mortality than conventional risk factors such as obesity, high blood pressure, and insulin resistance. The most accurate prediction of mortality can be made when VO2 max is tested in conjunction with these other risk factors.7

Dr. Patrick recommends "exercise snacks" as a convenient alternative to structured exercise at a gym. Avoiding prolonged sitting by quickly ascending 60 steps of stairs as quickly as possible every few hours can result in significant improvements in cardiovascular fitness. Dynamic warm-up, including 10 jumping jacks, 10 air squats, and five lunges on each side, and a one-minute walk for cool-down will facilitate these "snacks."8

Aerobic exercise may even have benefits for cancer prevention and treatment. Scientists used a bio-mimicking circulatory system to recreate the environment of intense and low-intensity exercise to test its effects on cancer cells. The results showed that when cancer cells were in a high-intensity exercise environment they were able to be killed significantly better than in a low-stress environment. The cancer cells were killed by exercise-induced stress, while normal cells were unaffected.9 In colon cancer patients, a small clinical trial found that any intensity of exercise significantly reduced circulating cancer cells after six months.10

Metabolic Flexibilty and Aging

John P. Thyfault, PhD (Professor of Cell Biology and Physiology at the University of Kansas Medical Center) studies the effects of fasting and exercise on metabolic health.

For people who are not exercising, after a meal the liver stores glucose as glycogen, which can provide glucose as an energy source for 10-14 hours. After that time, the body begins to use stored fat as energy. However, an hour of medium-intensity aerobic exercise, such as running, even four hours after a meal may be enough to start burning fat.11 The ability to switch from glucose to fat as an energy source ("metabolic flexibility") is enhanced by exercise but can be adversely affected by a poor diet. Animals fed high amounts of fat and sugar show impaired learning and memory,12 which may be counteracted by exercise.

Dr. Thyfault noted that insulin resistance plays an important role in reducing metabolic flexibility.13 Getting 150 minutes per week of moderate to vigorous exercise will reduce the risk of type II diabetes by 30%.13Insulin sensitivity declines rapidly within 24 to 48 hours after physical movements regardless of intensity.14 Even low-intensity exercise is sufficient to mobilize fat from fat cells, as well as increasing release of glucose from the liver.13,15

Although aging is associated with increased insulin resistance and reduced metabolic flexibility, Dr. Thyfault contends that it is the chronic inactivity equally associated with getting older, compared to aging itself, that results in these effects.14

Benefits of Creatine

Eric Rawson, PhD (Professor of Health, Nutrition, and Exercise Science at Messiah University in Mechanicsburg, Pennsylvania) has devoted his career to studying the effects of creatine on the human body. Approximately 95% of the creatine in the human body is found in skeletal muscle, where it makes energy rapidly available.16

The major source of creatine in the diet is meat. Creatine content in muscle is lower in vegetarians and the elderly. For this reason, creatine supplementation increases muscle creatine much more in the elderly and in vegetarians than in young people or meat-eaters.17,18

Creatine supplementation combined with resistance exercise increases muscle strength and reduces fatigue more than exercise or supplementation alone.19 Some studies presented in a review paper show that creatine supplementation combined with resistance training produced beneficial impacts on bone health.20

Creatine is important for brain function, although the brain can synthesize creatine and is therefore less dependent on other organs; however, it responds to supplementation. Research shows that creatine supplementation may increase brain creatine content by 5%-15%.21 Creatine supplementation has been shown to be more beneficial for memory in vegetarians than in meat-eaters.22

Creatine is safe and well tolerated in dosages up to 30 grams daily for five years. However lower dosages may be all that are required.23 One study found that 8 grams daily for five days reduced mental fatigue on a math test and increased oxygen utilization to the brain.24

Concluding Remarks

Most people understand that exercise contributes to health and longevity. Learning the mechanisms and conditions by which this occurs may increase people’s motivation to exercise.

The effects on cognitive health are less often recognized, so it is worthwhile to learn about these benefits from experts.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

References

  1. de Barcelos GT, Heberle I, Coneglian JC, et al. Effects of Aerobic Training Progression on Blood Pressure in Individuals With Hypertension: A Systematic Review With Meta-Analysis and Meta-Regression. Front Sports Act Living. 2022;4:719063.
  2. Bacon AP, Carter RE, Ogle EA, Joyner MJ. VO2max trainability and high intensity interval training in humans: a meta-analysis. PLoS One. 2013;8(9):e73182.
  3. Hov H, Wang E, Lim YR, et al. Aerobic high-intensity intervals are superior to improve V̇O(2max) compared with sprint intervals in well-trained men. Scand J Med Sci Sports. 2023;33(2):146-59.
  4. de Oliveira-Nunes SG, Castro A, Sardeli AV, et al. HIIT vs. SIT: What Is the Better to Improve V O(2)max? A Systematic Review and Meta-Analysis. Int J Environ Res Public Health. 2021;18(24).
  5. Gibbons TD, Cotter JD, Ainslie PN, et al. Fasting for 20 h does not affect exercise-induced increases in circulating BDNF in humans. J Physiol. 2023;601(11):2121-37.
  6. Clausen JSR, Marott JL, Holtermann A, et al. Midlife Cardiorespiratory Fitness and the Long-Term Risk of Mortality: 46 Years of Follow-Up. J Am Coll Cardiol. 2018;72(9):987-95.
  7. Ross R, Blair SN, Arena R, et al. Importance of Assessing Cardiorespiratory Fitness in Clinical Practice: A Case for Fitness as a Clinical Vital Sign: A Scientific Statement From the American Heart Association. Circulation. 2016;134(24):e653-e99.
  8. Islam H, Gibala MJ, Little JP. Exercise Snacks: A Novel Strategy to Improve Cardiometabolic Health. Exerc Sport Sci Rev. 2022;50(1):31-7.
  9. Regmi S, Fu A, Luo KQ. High Shear Stresses under Exercise Condition Destroy Circulating Tumor Cells in a Microfluidic System. Sci Rep. 2017;7:39975. Brown JC, Rhim AD, Manning SL, et al. Effects of exercise on circulating tumor cells among patients with resected stage I-III colon cancer. PLoS One. 2018;13(10):e0204875.
  10. Mattson MP, Moehl K, Ghena N, et al. Intermittent metabolic switching, neuroplasticity and brain health. Nat Rev Neurosci. 2018;19(2):63-80.
  11. Mattson MP, Arumugam TV. Hallmarks of Brain Aging: Adaptive and Pathological Modification by Metabolic States. Cell Metab. 2018;27(6):1176-99.
  12. Thyfault JP, Bergouignan A. Exercise and metabolic health: beyond skeletal muscle. Diabetologia. 2020;63(8):1464-74.
  13. Cao X, Thyfault JP. Exercise drives metabolic integration between muscle, adipose and liver metabolism and protects against aging-related diseases. Exp Gerontol. 2023;176:112178.
  14. Bird SR, Hawley JA. Update on the effects of physical activity on insulin sensitivity in humans. BMJ Open Sport Exerc Med. 2016;2(1):e000143.
  15. Bonilla DA, Kreider RB, Stout JR, et al. Metabolic Basis of Creatine in Health and Disease: A Bioinformatics-Assisted Review. Nutrients. 2021;13(4).
  16. Solis MY, Artioli GG, Otaduy MCG, et al. Effect of age, diet, and tissue type on PCr response to creatine supplementation. J Appl Physiol (1985). 2017;123(2):407-14.
  17. Cooper R, Naclerio F, Allgrove J, Jimenez A. Creatine supplementation with specific view to exercise/sports performance: an update. J Int Soc Sports Nutr. 2012;9(1):33.
  18. Gualano B, Rawson ES, Candow DG, Chilibeck PD. Creatine supplementation in the aging population: effects on skeletal muscle, bone and brain. Amino Acids. 2016;48(8):1793-805.
  19. Antonio J, Candow DG, Forbes SC, et al. Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? J Int Soc Sports Nutr. 2021;18(1):13.
  20. Dolan E, Gualano B, Rawson ES. Beyond muscle: the effects of creatine supplementation on brain creatine, cognitive processing, and traumatic brain injury. Eur J Sport Sci. 2019;19(1):1-14.
  21. Forbes SC, Cordingley DM, Cornish SM, et al. Effects of Creatine Supplementation on Brain Function and Health. Nutrients. 2022;14(5):921.
  22. Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18.
  23. Watanabe A, Kato N, Kato T. Effects of creatine on mental fatigue and cerebral hemoglobin oxygenation. Neurosci Res. 2002;42(4):279-85.