I have been interested in exercise, nutrition, and athletic performance for quite some time. In the past few years I have contemplated the relationship of these topics to disease prevention and life extension (both quantitative and qualitative). I would like to share some ideas about how to maximize longevity and fitness. To do this I will provide a brief look the factors which govern these states and then make a few recommendations that anyone can implement with a little effort.
The only sure means of increasing longevity to date has been Caloric Restriction with Adequate Nutrition (CRAN). An excellent review of CRAN can be found at http://herc.org/news/mcsarticles/frame.htm however I will cover a few of the key features of CRAN here. Keep in mind that virtually all of the studies on CRAN have been done on rodents. A few have recently been completed on primates and a human trial is underway but meaningful data from these studies will not be available for years.
Common features of CRAN include: caloric restriction levels between 30-50% of ad libitum fed controls. Body mass index as well as body fat percentage decrease considerably. Initially there is a significant Hypercortical response which leads to increased insulin sensitivity, decreased inflammation, increased apoptosis, and an increase in DNA repair enzymes to name a few of the major effects. A decrease in mitogenic factors such as insulin, estrogen, and testosterone is also common although not universal as is decreased body temperature.
What one accomplishes with this protocol is a decrease: in the likelihood of: cancer by enhancing apoptosis and minimizing growth promoters, in diabetes by enhancing insulin sensitivity, of heart disease by reducing inflammation and minimizing Advanced Glycation End-products (AGE), and autoimmunity by beneficially modulating immune function. Low body-fat levels are beneficial for decreasing growth promoters such as estrogen and for minimizing oxidative stress.
Fitness, as defined by the October 2002 issue of the Crossfit Journal: http://girevikmagazine.com/Girevik/Five/CFJ%20Oct%2002%20Fitness.pdf is greatly affected by nutritional status and training protocol. This is particularly intriguing if one considers that it is possible to optimize immune function, minimize inflammation, and optimize protein and calorie utilization via caloric restriction.
For fitness AND longevity however we must mitigate one major feature of caloric restriction: loss of muscle mass. Muscle mass maintenance and acquisition is best accomplished by training in a manner which maximizes the neuro-endocrine response (NER).
NER is a term which describes the release of growth hormone (hGH), insulin like growth factor (IGF), and Testosterone as a consequence of exercise. On a whole these growth factors promote growth and maintenance of muscle and internal organs by increasing protein uptake from the intestines and improved nitrogen retention. It is interesting to note that it is an excess of insulin, IGF and other growth factors in a hypercaloric (overfed) state which is implicated in many degenerative diseases. Training protocols such as Crossfit, Evolutionary Fitness, and the Russian Kettlebell Challenge all have elements which elicit a profound NER: multi joint, integrated movements such as sprints, Olympic lifts, squats, dead lifts, and kettlebell swings.
It is my contention that one may optimize both longevity and fitness by a synthesis of CRAN and the NER. As there exists ample information regarding the training considerations of this plan I will focus on the nutritional and lifestyle factors which will optimize your results.
CRAN-Caloric Restriction need not mean starvation and must meet the requirement of Adequate Nutrition. This means adequate protein, essential fatty acids, vitamins and minerals. Non-essential but highly beneficial phyto nutrients which act as antioxidants, antimutagenic, and pro-apoptotic agents will factor highly into optimizing health and longevity.
I will use a paper by Prof. Loren Cordain, which is available in its entirety here: http://www.thepaleodiet.com/articles/JANA%20final.pdf to describe a reasonable approach to CRAN. Three main meals and several small snacks are consumed. The representative diet provides 2200 kcal, 217 g of protein, 129 g of carbohydrate, 42 g of fiber, 100g of fat with 9.6 g of n-3 fatty acids and an n-6/n-3 of approx 1.5-1 which is considered ideal. The carbohydrates consumed are mainly fruit and have a high ORAC (Oxygen Radical Absorbance Capacity) and a low glycemic load. With the exception of calcium and vitamin-D the diet supplies several times the RDA of all nutrients. A thorough reading of the article reveals that no deficiency exists when on accounts for endogenous production of vitamin-D from sunlight exposure and positive calcium balance due to a net alkaline load provided by the diet. It should be clear that following a Paleolithic diet will virtually guarantee moderate CRAN while providing ample nutrients for growth and repair.
A few final considerations for optimizing CRAN/NER. Sleep at least 9 hrs in a completely dark room especially during the winter months. Read the book Lights Out: Sleep, Sugar, and Survival for more details. Intermitant fasting is helpful and can be accomplished by eating all of ones meals as early in the day as possible. This will allow for as much as 15 hrs of fasting with the bulk of it spent in sleep. An occasional day long fast can also be part of your plan.
I hope you find this information helpful. For further reading on these topics I would recommend the Foundations page of CrossFit, the Russian Kettlebell Challenge, The Omega Rx Zone, EvolutionaryFitness, and Natural Hormonal Enhancement.
Good Luck!