eNutrition 101
a LaFrance Consulting Services™ e-Course
Nutrition for Liberal Arts Students, independent study

Fitness and Sports


A prerequisite for any program of “intentional physical activity” (Roizen & Oz) designed to improve fitness is a degree of wellness. Earlier, we defined wellness as “the absence of disease processes.” Specifically we need to make certain that any person has sufficient cardiovascular and respiratory wellness before they are encouraged to begin the “behavior modification” leading to a less sedentary life style. At the same time, we must note that fitness, defined as “the ability to exercise without negative health consequences,” contributes to an increase in over-all wellness. This circular dependency leaves us with a classic ‘catch-22:’ you can't improve fitness if you don't have wellness, but you can't develop a high level of wellness without fitness. The solution is to develop a multi-phase program where the intensity of the intentional physical activity increases as the improved fitness contibutes to an increase in cardiovascular and respiratory wellness. We have found that most Humans who don't get enough exercise are quick to explain that they don't have time to exercise. I choose to accept their explanations, then try to show them where to find the time [at least a few of my former students in Nutrition have temporarily increased their activity levels, at least until the demands of the Nursing program provided the excuse they needed to resume their old sedentary ways. A small amount of treachery is needed to trick most people into getting exercise. For starters, we know that we want them to get more exercise, so we won't tell them to exercise. The term exercise is usually understood to mean “vigorous, structured, and planned activity [at a gym and led by a drill sargent personality].” On the other hand, physical activity defined as “any and all use of muscles beyond ADL's,” does not bring to mind the vivid imagery of exercise [for those of us who remember Phys Ed in public schools]. Many people who ‘don't have time to exercise,’ may consider increasing their physical activity; for example, instead of parking in the space closest to the door [at commuter College classes; at shopping malls or grocery stores] and walking the extra distance. Similarly the best way to deal with drive-through restrauants is to avoid them altogether; but the second best way to deal with them is to park further from the door than is necessary; walk in and place your order at the counter; stand (or walk around) to wait for your order, then find a table where you can eat (slowly); then walk back out to your car.

Introducing physical activity to a sedentary population

Phase 1 (stamina training)

We are easing the previously sedentary Human into increased physical activity to improve cardiovascular and respiratory wellness, so they can begin to be active. At first, we would like to see 3 days a week, with 30 minutes (in three 10 min intervals) of mild to moderate activity [having stated that we want physical activity 3 days a week, we expect to actually get only 1 or 2, but any is better than none]. Generally, walking at a comfortable pace (supporting conversation), beginner Pilates mat exercises (the ones listed as warm-ups for subsequent exercises), swimming, or other similar non-strenuous, low impact activities (the 12-ounce curl [drinking beer] doesn't count). No resistance is allowed at this point (bicycle, rowing, weights or elastic bands, gym equipment of any kind, and so forth). The metabolic cost of this level of activity is about 200 Calories per 30 minutes, and the candidate for wellness should be instructed not to exceed 30 minutes [no real reason, just treachery to encourage cooperation; to be un-cooperative with these instructions, the they will have to remain active more than 30 minutes!]. The 200 Calorie cost applies to plantigrade [heel first] walking; digitigrade [toe first] walking will cost you 230 Calories. After about two weeks, the you could (at your discretion) add a fourth day a week of similar activity [where the ‘fourth’ day will probably be a second or third], and a fifth after two more weeks of four times a week. After four weeks total (whether or not you increase above 3 times a week) you can increase the pace as long as you can still carry on a conversation at the faster pace.

Phase 2 (strength training)

For people who were physically active no more than 20 years ago, their cardiovascular - respiratory systems should have recovered reasonably well [even at a pack a day of smoking] to allow moving to Phase 2 after four weeks of phase 1 activity. Those who were hoping to have their heart attack no older than about 35 to 53 years and were maintaining a life style designed to achieve that goal, should see their doctor to have their cardiovascular and respiratory health rechecked before moving up to Phase 2. We are now going for some anaerobic activity; 20 minutes anaerobic 1 or 2 days a week, plus enough Phase 1 activity to make a total of 3 days of activity a week [yes, I know I hinted that you should be up to four or more days a week by now, but we both know “that ain't gonna happen”]. Walking is to be a brisk walk (preferably digitigrade), swimming is now laps (with ‘catch your breath’ breaks as needed), jogging (must be digitigrade, unless you really want to become crippled so you can hardly waddle along at 1 mile per hour with a cane or walker [or perhaps even on your Hoveround™ power chair], but that seems inconsistent with the Hippocratic oath: do the patient no harm). The metabolic cost of this activity should be about 300 Calories per 20 minutes. As before, the brisk walk will cost 300 Calories if plantigrade and 345 Calories if digitigrade. There is no difference in metabolic cost for jogging plantigrade or digitigrade [running always involves muscles of the body core and fine motor skills muscles of the legs to maintain balance]. Walking digitigrade also involves all of the same muscles as running, while plantigrade walking does not, which is why plantigrade hikers (in mountainous terrain) have a higher incidence of sprains than do digitigrade hikers (personal experience).
    Two features must be added to the activity due to the higher level at which the activity will be taking place: we need a warm-up and a cool-down. The 5 minute warm-up involves both a warm-up in the usual athletic sense and stretching [which is what calisthenics were back during once upon a time … ]. Stretching, by alternately flexing and extending slowly those joints where movement will occur during the activity, increases flexibilty of the joint enough to minimize the risk of joint injury. Warm-up slowly increases the pulse rate to active levels, minimizing the risk of an abrupt change in heart rate causing a heart attack. After the 20 minute activity work-out [again no more to encourage cooperation with the program, and no less or the desired fitness benefits may not be realized], we require a cool-down, in which the same muscle groups are worked gently for 5 minutes. The cool down serves to maintain the elevated pulse rate (and blood volume) long enough to metabolize most of the lactic acid back to pyruvate for burning in the citric acid (Krebs) cycle. [Note also: we have told you that you only have to engage in the activity for 20 minutes (and it replaces the 30 minutes from Phase 1), but with a 5 minute warm-up and 5 minute cool-down, you still get 30 minutes of activity. We are still calling it physical activity not exercise because ‘activity’ is less intimidating than ‘exercise’ [that High School PhysEd teacher-slash-drill sargent pretty much cured us of the desire to exercise; besides it's like algebra - we just knew we'd never use it after H.S. graduation].

Phase 3

In phase 3, we introduce resistance. We are not talking “pumping iron” here, we simply want to increase the intensity of the exercise safely [as in do not harm the patient]. We can replace one of the phase 2 activities with 30 minutes (as three repetitions of 10 minutes each) of resistance. This can be bicycling (even on a stationary bicycle), rowing, or a work-out with resistance bands. However, the simpler, and more patient friendly version is pilates or Yoga. Yes, Yoga counts as resistence training (Roizen & Oz. You, the Owners Manual, Harper Collins, 2005. p. 124ff). An activity you can try at home [as in right now!] is modified “deep knee bends”. Stand up, place your hands on your hips (or waist); now lower your body about 3/4 of the way down [do not go all the way down - that funny popping noise from your knees is proof that you just did some joint damage!]; then come back up to a standing position. Now repeat the deep knee bend; but go down as slowly as you can, then come back up as slowly as you can. Did you feel the difference? It took far more effort, and your muscles should have felt it (and may even feel a bit more tired). So, what happened [rhetorical question]; to do a deep knee bend (or any other calestentics-type activity) slowly involves opposing muscle pairs (plus fine muscles for balance), where the opposing muscle for the activity provides the resistance. Again you are working more than twice as many muscles, but not quite doubling the Calorie cost. I did some research on a Pilates web site, and discovered that Pilates is modified Yoga [for the Western mind-set; Yoga was designed for the far Eastern mind-set]. I highly recommend either as the prefered resistance activity for previously sedentary patients.


In the above discussion, I have obviously emphasized walking as the preferred wellness activity, partially because it is easy to do, and requires no special equipment [you don't even need those expensive ‘walking’ or ‘cross training’ shoes; are the other shoes for sitting or for serious remote control action?]. In case you didn't guess yet, it is also my favorite form of exercise. I tend to walk over 10,000 steps a day; and generally manage to go about 5,000 steps on slow days. When I was a young adult of about 20 years of age, I did a lot of mountain hiking [for which I got paid as a nature counselor at Philmont Scout Ranch in New Mexico], where I hiked an estimated 3,000 miles per summer for four consecutive summers. On one occassion, on a 45 mile trail measured by bicycle wheel, and using a stop watch, I calculated my average hiking speed to be 7.5 miles an hour. I did not believe the number until I later read that in a walking race in Chicago, the winner averaged 7.6 miles an hour; so Humans are capable of walking that fast. In fact based on my personal experience, I believe that the Human body is designed to sustain a 4 mile/hour pace (7,500 to 8,000 steps per hour) indefinitely, by starting after breakfast and walking for two hours before taking the OHSA 10 minute break, than walking another two hours before stopping for lunch. After lunch, walk another two hours before the OSHA break, and two hours before stopping for supper and for the night. One would hike 32 miles per day at this pace, and it would take 94 days to cover 3,000 miles [the approximate distance from New York City to San Francisco], and you would not be exhausted at the end of the journey, assuming you have sufficient fitness at the start. As a species, we began in Africa (the Oldavi gorge area near the south end of the Red Sea is the site of the oldest known modern human fossils; near the Garden of Eden, if you prefer) yet managed to spread to most of the globe before inventing the wheel, meaning we moved on foot and by canoe [southern Chili and Argentina are about 40,000 miles from Africa by the land route across Asia to Siberia and Alaska, then down to the southern tip of South America].
    The most obvious support for the benefits of such activity is that I have been described by a medical doctor reviewing my health screening results as being “disgustingly healthy for a man my age.” I have also been accused by a medical doctor, reviewing the results of my exit physical exam from a quasi-government job, of being an athlete (which I am not).
    That walking is my favorite exercise activity is an important point: The best exercise is one you enjoy, so you will continue to do it for years. To summarize the importance of intentional physical activity as a slogan: “The ability to exercise, either aerobic or anaerobic, depends on adequate balanced nutrition; and Wellness is improved by a combination of adequate balanced nutrition and regular exercise.


Sports in this context refers to actual athletes engaged in a sport other than amateurs entered in a marathon. If you intend to enter several marathons, you can be considered to be an athlete; but entering a single marathon for charity does not qualify you for athlete status [you are merely engaged in a more strenuous version of phase 3 intentional physical activity, which has only a temporary impact on your nutritional needs]. To illustrate this point, I recommend that you watch (part of) the television coverage of a marathon. Within the first few tens of yards, a group will separate at the front. Most members of the lead group will be runners, who tend to run digitigrade; while the larger trailing group will include many joggers who tend to run plantigrade. If you watch their feet as they run you will be able to see the difference [you will also be able to become bored because marathon races are not real exciting, unless you are a marathon runner who is not entered in this race]. After the first several miles (this is a 26.2 mile run), there will be a small group of runners out front, a gap followed by additional small groups separated by gaps. The last trailing groups, far behind the leaders, are the amateurs who are not athletes. For example, in the “Race of Champions Marathon” in West Springfield, MA on May 3, 2009 [this is a qualifying run for the Boston Marathon, data downloaded on 5/6/2009 3:23 pm from http://www.marathonguide.com/results/index.cfm] there were only 82 finishers, grouped (by me) as follows [groups defined as separated by more than 1 standard deviation (4.75 minutes) in average separation for all finishers]:

1within group (minutes)
2from prev. group (minutes)
3less than walking race winner
4hiking speed (dedicated hiker)
Race of Champions Marathon
May 3, 2009
avg separation1
7 3.00 0.00 9.33
1 0.00 11.03 8.44
12 2.40 5.07 7.94
37 1.15 5.82 6.563
13 1.10 7.93 5.89
2 4.08 8.88 5.51
2 4.72 6.02 5.31
2 3.17 13.97 5.01
1 0.00 5.32 4.90
2 0.00 23.25 4.57
1 0.00 11.53 4.42
1 0.00 6.58 4.34
1 0.00 30.33 4.014

If you thought I was kidding when I called this a boring race, it took 32.03 minutes after the winner crossed the finish line before the eighth runner arrived at the finish. The last runner across the finish line arrived
6 hours 32 minutes and 29 seconds after the race started.
and the racers don't even ‘bump draft’ or crash into the wall on turn 2!

Energetics of sports activity

We shall first examine the physiology of athletes, so we can discuss the unique nutritional needs of of the athlete. The intensity and duration of the physiological demands on the patient directly affect the energy sources utilized, and therefore the mechanisms for replacing the energy expended.


Intensity is generally classified as: light, moderate, and intense (or strenuous). No sports involve light intensity, even golf with golf carts. Moderate intensity allows carrying on a casual conversation; but remember that athletes have better cardio-vascular health than most of us, so they can carry on a conversation at a higher intensity than can non-athletes. Under intense (strenuous) activity it is no longer possible to carry on a conversation without “pausing to catch your breath,” although athletes can communicate effectively with few words, such as “I'm open [to receive a pass]” in basketball or soccer, or “Man on” in soccer to mean that an opponent is approaching.


Duration refers to how long the activity continues at the present level of intensity. A short duration is 10 minutes or less; moderate duration is 10 to 20 minutes; long is over 20 to 45 minutes. Anything over 45 minutes is considered to be “endurance,” as frequently occurs in basketball and soccer (football or “futbol,” outside the United States). These numbers are directly related to the energy sources utilized.

Energy sources utilized

During the 1st 10 minutes of moderate to intense activity, the conversion of stored [in muscle] glycogen to glucose provides the major energy source. For the 2nd 10 minutes, energy demands are met by a shift to serum glucose with a reduced demand on glycogen stores. After 20 minutes, the muscles begin using [mostly] serum fatty acids [may be converted in muscle to glycogen] supplemented by serum glucose plus conversion of serum glycogen. After about 45 minutes the muscles must rely heavily on dietary carbohydrates [from short term storage in liver] for serum glucose, and on serum fatty acids supplied from adipose, because glycogen stored in the muscle tissue will be exhausted. It is generally believed among athletes that “carb loading” can provide the dietary reserve for endurance sports, and there is now research to support this (Currell K, Conway S, & Jeukendrup AE. 2009. “Carbohydrate ingestion improves performance of a new reliable test of soccer performance.” Int J Sport Nutr Exerc Metab. 2009 Feb;19(1):34-46.) plus an older review article (Williams C, & Serratosa L. 2006. “Nutrition on match day.” J Sports Sci. 2006 Jul;24(7):687-97.). [Abstracts of both of these can be found at PubMed.gov and searching for “carbohydrates, soccer performance”].
After the sports activity has ended, adipose fat will be utilized, if there is sufficient adipose fat, to replace stored glycogen, probably both in muscle and liver. As for intentional physical activity, this adipose mobilization is only partially controlled by the liver, via the vagus and symphathetic nerves, but it appears that serum lactic acid in the adipose may also trigger this. Fat mobilization may continue up to 2 hours after the activity, or until adipose reserves reach the minimum permittted by the individual (genetics may determine this).

Long term effects on physiology

If the sports activity is continued for 2 to 3 months, there will be growth of new mitachondria in the active muscle tissue, increasing basal metabolism. Muscles require 75 - 150 kcal/lb/day at rest, compared to the 3 kcal/lb/day for adipose. The added mitachondria serve to provide ATPs faster, to meet the energy demands of the sports activity. When lactic acid is detected, probably by the hypothalamus, the “anabolic effect” is triggered; the pituitary will stimulate the production of anabolic steroids, which in turn drive the growth of muscle cells [and for anabolic steroids produced in the body, they drive a matching increase in bone density (and strength) which OTC and street steroids don't do]. It is the growth of new muscle tissue which is responsible for the “soreness” of the muscles the day after the sports activity. This has two important implications for the patient. First, an increase in intake of dietary animal (red meat) protein and the associated animal fats [both are critical to supporting the muscle growth; fats contribute to glycogen replacement]. The second issue is that when weights are involved in the training, the muscles should NOT be worked when the soreness due to muscle growth is occurring - as the muscles are growing, they are more susceptable to injury (muscle tearing) leading to scar tissue forming in the muscle. The scar tissue in the muscle will weaken the muscle, defeating the purpose of developing the muscles by weight training. The primary energy source for muscle growth is adipose [when present in sufficient quantity, and dietary fats when adipose reserves are insufficient].

Nutritional needs for the athelete

The traditional “training table” diet, still considered to be good, is high in untrimmed [fat left on the meat] red meats, and high in vegetables (for vitamins). The traditional high carb aspect of the training table diet is probably unnecessary. Sufficient carbs to complete the calorie intake from fats, or recommended minimum daily intake, (whichever is higher) should be enough. “Carb loading” from 24 to 3 hours before a match has been shown to provide available energy for endurance sports, based on clinical evidence. In any event, carb loading within one hour of the event is not a good practice. Carb loading should always involve complex, not-easily digested [low glycemic index] carbohydrates. Sugars should be avoided due to the “sugar crash.” Snacking during the match should not be considered, except during breaks in an endurance sport [soccer and basketball half time]. It is common to consume high carbohydrate snacks during marathon running, but I suspect the primary effect is to slow the runner down while they are eating, so if the participant hopes to win the marathon, they should probably avoid the snack food [if they want to enter, and then lose… ]. Protein bars and drinks [marketed as an energy boost] do not provide useable energy, nor should athletes (or other Human-like creatures) ever consider consuming them. For youth sports, the best snacks for after the event would be fruits (for their water and mineral content).
    100% of water lost (sweating) must be replaced as soon as possible after the event is over [and,for youth sports, any time the participant is off the field]. Atheletes can lose as much as 22 lb, or 10 kilos H2O as sweat. The water should not be chilled due to a high risk of thermal shock. Salty carbohydrate snacks can be used to help youth athletes get adequate water since they won't like unchilled beverages. Especially for youth sports, drinks high in high fructose corn syrup must be avoided [any sugared drink is unacceptable]. Anyone who has ever tasted sweat knows how salty it tastes [due to lost electrolytes]. The electrolytes lost in sweat must also be replaced along with the water to avoid heat exhaustion.
    NO performance drugs should ever be allowed. Over the counter [and “street”] anabolic steroids are extremely dangerous, and should never be permitted nor tolerated by any athletes, amateur nor professional! Naturally produced anabolic steroids [those produced by the athlete himself or herself in response to the activity] cause matched growth in muscle and bone density. Synthetic anabolic steroids stimulate muscle growth without associated increase in bone density, so the athlete can actually break bones simply by contracting their muscles. The most famous example occurred at an Mr. America [weight lifters] pagent, where one participant fell down, writhing in pain from a greenstick fracture of the upper arm caused by simultaneous contracting the biceps and triceps. The biceps was stronger than the triceps, bending the humerus beyond the breaking point. Any product marketed as a boost to athletic performance is to be avoided. The “energy drinks” have as the active ingregients sugar and caffeine, neither of which boosts energy, but can increase systolic blood pressure to dangerously high levels, given that the athletic performance already involves increased systolic blood pressure.

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