This is a continuation of the prior posts: Dietary Restriction: Impact On Health And Longevity, which summarized the benefits of caloric restriction (CR), Protein Restriction Increases Longevity, and Periodic Fasting Increases Health And Longevity. This post will deal with another alternative to CR, CR plus exercise.
Caloric Restriction Combined With Exercise (CE) In Animals1
"Some studies have found that CE does not elicit health-promoting benefits beyond those elicited by CR." There were a few benefits, mostly muscle-related: "CE has been shown to attenuate age-related sarcopenia. ... CE reduces muscle fatigue and may increase the oxidative capacity of muscle fibers." And CE may reduce levels of C-reactive protein."
"The addition of exercise to a CR regimen does not appear to affect an animal's maximal life span."
Caloric Restriction Combined With Exercise (CE) In Humans
"Many human CE studies have incorporated a total caloric reduction of 25%, with 12.5% coming from exercise-induced expenditure and another 12.5% coming from reduced caloric intake (i.e. diet)."So, there was little additional benefit gained by appropriating some caloric deficit to expenditure, except that seen in bone and muscle, two areas where the benefits of CR alone were lacking ("Unfortunately, CR does not appear to retard the age-related loss of bone and muscle mass."). Those are still mighty important areas when it comes to quality of life and living independently. Also, adding exercise might help achieve CR without extremely cutting caloric intake. Unfortunately, exercise has a profound effect on appetite.
"Many investigations have noted no significant difference between CE and CR regarding their respective effects on fasting insulin levels, DNA damage, muscle mitochondrial gene expression, triglyceride levels, and liver lipid content."
"Two investigations have noted a further reduction in both diastolic blood pressure and LDL cholesterol with CE when compared to CR alone [67,89]."
"Other work has noted that CE improved insulin sensitivity, while CR-alone failed to do so."
"CE has been shown to increase bone mineral density at the femoral neck."
"Collectively, although results are somewhat mixed, it appears that the addition of exercise to a CR plan may provide further health benefits."
- Caloric restriction (CR) of at least 20% extends life and improves health.
- Protein restriction, but not carbohydrate or fat restriction, offers similar benefits to CR. The amino acid methionine, found primarily in animal food, is likely responsible for this.
- Periodic fasting offers some benefits and has been shown to extend life in animals, but research, especially in humans, is sparse.
- Adding exercise to a CR regimen offers little additional benefit save for improvements in bone and muscle.
This was one in a series of 4 posts:
- Dietary Restriction: Impact On Health And Longevity
- Protein Restriction Increases Longevity
- Periodic Fasting Increases Health And Longevity
- Additional Health Benefits From Adding Exercise To Diet
Photo of man walking in Segovia, Spain from Slight Chance Of Pixels.