N u r t u r e F o o d s

Transcription

1 Tips on Timing of Diet, Weight Loss, and Exercise 1. Hydrate before you exercise to get the most out of your workout The goal here is to make sure your body has a balanced amount of electrolytes and fluid to carry you through your workout. For if you are dehydrated, recent guidelines provided by the American College of Sports Medicine in 2007 states that dehydration increases physiologic strain and perceived effort to perform the same exercise task. To appropriately maintain hydration, it is recommended that an average 70kg male consume 12-16oz of water approximately four hours prior to exercising. If you do not urinate or your urine is dark, then consume another 7-12oz of water two hours prior to exercising. The importance of hydrating several hours before you exercise is to provide sufficient time for fluid absorption and to allow urine output to return to normal so you won t have to run to the restroom during your exercise routine. Hyperhydration has not been demonstrated to provide a clear physiologic or performance advantage and in fact may harm you by causing a state of hyponatremia which in some rare cases can lead to hospitalization or death. 2. Maximize a healthy diet by not timing your dinner to TV shows A 2007 study in the Journal of Nutrition and Educational Behavior confirmed that eating in front of the TV as opposed to family type meals had a negative impact on dietary intake in adolescents that has been found to transcend to adults in other studies as well. This is believed to be due to the abundance of advertisements on TV promoting unhealthy food and particular soft drinks. By eating as a family without the TV on, adults can pass on healthy eating habits to their children by having a greater influence on what they are consuming. 3. Protein before or after a weight-lifting session Long debated, much of the research points to having your protein load after your workout with the weights. Protein synthesis to create more muscle is increased after a session of weight-lifting provided the stimulus is of sufficient intensity. This transient increase is marked, but has a time span of approximately 48 hours. However, the closer you get to the 48 hour mark, the less amount of protein is synthesized. Thus as protein administration is crucial for an optimal effect on muscle building, an early intake of protein after exercise is recommended. 4. Aerobic or resistance exercise which to do first?

2 Many people combine cardio and weights on the same day of their exercise routine for several reasons. Some even have a sequence to how they do their exercises, cardio before weights or vice versa. Is there scientific evidence that one done before the other actually has more benefit? A study in the Journal of Strength and Conditioning Research examined a small group of men who completed exercises in the following format: resistance only, run only, resistance-run, and run-resistance. Results demonstrated that when running was performed before resistance training, EPOC (excess post exercise oxygen consumption that contributes to burning more fuel) was greatest. Furthermore, if resistance training preceded cardio, their cardio phase of the workout was perceived to be more difficult. Keep in mind, that this study was extremely small (10 subjects) and the same 10 subjects were used in all four groups of exercises with at least two days separating the different exercise types. With that said, the recommendations from the authors are to perform aerobic activity before resistance training in those combining both activities in their workout. 5. Stretching before or after Exercise? Many people stretch before or after exercise for several reasons. Usually the purpose is to reduce muscle soreness or prevent injury. But does it really make a difference? The most recent systematic review of the medical literature was performed in 2002 in the British Medical Journal. Five studies met the author s criteria to be examined for the prevention of injury. Of the five, three studies evaluated stretching before exercise while two investigated stretching after. Stretching time varied from seconds and were all done in healthy young adults. It was concluded that stretching, either before or after exercise, had no statistically significant effect on prevent later muscle soreness. 2 additional studies met the articles search criteria for investigating if stretching before exercise prevented injury. Both studies were performed in new military recruits and stretching ranged from seconds. Although a 5% decrease in injury was observed in those individuals who stretched as opposed to those who did not, this was not a statistically significant difference. When compared to other reviews in the medical literature, these results confirm findings from a different review but contradict a few others. It may be more prudent to state that although stretching before exercise may not decrease your chance of injury or soreness, it certainly does not make these symptoms worse. 6. When should I take my MVI? Multivitamin (MVI) supplement refer to any product containing 2 vitamins with or without minerals and with or without herbal or botanical components. There are many different combination and preparations of multivitamins, some specifically enriched with Vitamin Bs, some enriched with iron, while others are

3 focused to prevent certain diseases (i.e beta carotene levels for eye care). Many studies have been performed to assess the best time to take these pills which will optimize absorption of MVIs. While there have been some conflicting opinions, many of nutrition experts would concur that MVI should be taken with a meal (preferably within 30 minutes following completion of a meal). There is NO difference whether this is breakfast, lunch or dinner (however, in insomnia is an issue, try to avoid taking at dinner time as Vitamin B6 and B12 may cause sleeping difficulties with some people). There are two basic types of vitamins, water-soluble vitamins such as Vitamin Bs and Vitamin C, or fatsoluble vitamins such as Vitamin A, D, e and K. As with most water soluble vitamins, their storage in the body is limited (meaning that without adequate dietary supplementation from food sources, they are the most rapid to deplete); however, they are easily absorbed either with or without food. Conversely, the fat soluble Vitamins A, D, E, and K (typically stored in body fat and the liver) need to be taken with a meal that contains some fat for maximal absorption in the proximal portion of the small intestine (duodenum). One caveat, for those who supplement with fiber, make sure to take it at least 60 minutes before or after MVI supplementation, as fiber can bind with fat-soluble vitamins, affecting their availability for gastrointestinal absorption. Lastly, for MVI that are fortified with iron, avoidance of certain beverages (such as tea, coffee, and red wine) that are high in phenolic compounds is necessary as they may affect iron absorption. 7. Best time to take an oral contraceptive? Regarding oral contraceptives (OCP), there is no evidence for a best time to take them. Rather it is important to take them consistently at the same time everyday. If you do get nauseated taking OCP s on an empty stomach, taking it with food does provide relief. However there are no contraindications with the absorption of the OCP with any food you might consume. 8. Does it matter when I take Calcium? Current recommendations for taking calcium are 1,000mg/day for women between 25-50yo, increasing to 1,200-1,500mg/day for pregnant, lactating and postmenopausal women not on estrogen replacement therapy. Calcium intake is important to prevent the natural loss of bone density that occurs with age, which in women, is accelerated after menopause due to the decreased production of estrogen which helps to maintain bone mass. While calcium can be taken in many forms ranging from diet or calcium-fortified foods, many women choose to take it via supplement form. A general rule of thumb is to take your calcium supplement before or between meals. The reason for this is that there are several foods that can inhibit the absorption of

4 calcium. These include foods high in: phytic acid (found in whole grains), sodium and protein that can enhance urinary calcium excretion. Common supplements such as antacids (that contain aluminum) can bind to calcium increasing its loss through urine. It is also wise to divide your calcium intake instead of taking it all at one time as your body adjusts the amount of calcium absorption based on the amount in your diet. So in addition to taking your calcium supplement between meals, make sure the doses are no more than 500mg at a time. On the other hand, Vitamin D enhances calcium absorption and many calcium supplements come in a combination of Vitamin D and calcium. Calcium Citrate as opposed to Calcium Carbonate is the preferred supplement to take as a study in the Journal of Pharmacology demonstrated a greater bioavailability in Calcium Citrate. 9. When to take a nap? Nowadays it seems we live in a 24-hour society where often times, there are not enough hours in the day to get your work done. As a result, sleep deprivation and disruption are commonplace and napping has garnered much attention on potentially improving productivity. A recent scientific review of the napping literature was performed in 2003 in the Sleep Medicine Review Journal. Young adults between the ages of generally had the least amount of sleep as compared to older age groups. To no ones surprise, a survey concluded that 40% of young adults would consider napping at work if their employers allowed them to. However, employers may want to seriously consider this as laboratory studies demonstrated short naps (15min) after lunch increased alertness and cognitive performance even if subjects had as little as four hours of sleep the night prior. Studies have even indicated an optimal time to take a nap. Anecdotal evidence points to the greatest time of sleepiness as after lunch. A study examined a 25 minute nap commencing at 12:20 and observed that although alertness improved, no effect was seen on cognitive performance. However, a 27minute nap at 14:00 improved both alertness and cognitive performance. 10. I m thinking about getting pregnant, when should I start taking folate? Folate, or folic acid, is a vitamin that is essential in the development of your fetus. When deficient, it has been demonstrated to play a role in the development of neural tube defects (eg spina bifida). A large multicenter trial performed in the 1991 of 1817 women at high risk of having a pregnancy with a neural tube defect demonstrated a 72% protective effect in those women consuming a folate supplement.

5 What women need to know is that they need to start taking folate the moment the are thinking about getting pregnant and not when they are pregnant. The reason behind this is that neural tube formation of your fetus develops during the first 28 days after conception, often before a woman even knows if she is pregnant! Current recommendations from the US Public Health Services are for women capable of becoming pregnant to consume 400mcg of folate a day either as a supplement or through dietary sources. 11. Does it matter when I take my iron supplement? It is not uncommon for women of all ages to take iron supplements. In fact, iron deficiency is the most common nutritional deficiency worldwide. In particular, women of childbearing age or pregnant are especially susceptible to the development of iron deficiency which can lead to problems such as anemia. When you take iron in pill form, this is known as non-heme iron which is less absorbable than heme iron. The absorption of non-heme iron can be affected by what you are consuming with it. Two dietary factors that increase absorption of non-heme iron are ascorbic acid (vitamin C) and meat (including fish and poultry). Vitamin C aids in the absorption of iron by converting ferric to ferrous iron which is the easiest absorbable form of iron. Foods that inhibit iron absorption include phytic acid (found in whole grains), tea, coffee, calcium and soy products. If you notice, many of these foods are regularly advocated as part of a healthy diet. Does this mean you should avoid all these good and healthy foods if you are on iron supplementation? No! Luckily a small amount of vitamin C consumed with these types of foods is enough to counteract the inhibitory effects these foods have on iron absorption. So make sure you take your iron supplement with a glass of orange juice and you will ensure adequate absorption no matter what else you are eating. 12. If there is a time to increase my exercise during my menstural cycle, when would it be? Weight changes are often associated with your menstrual cycle and most often this is attributed to water retention. But is this the entire story? It has long been known that women are more susceptible to weight gain than men, but there is no one specific reason for this and most likely there will not be just one. Studies performed as early as the 1920 s have investigated if a woman s menstrual cycle may play a role in weight gain by altering a woman s resting metabolic rate (RMR). While some studies indicate a decrease in RMR one week before ovulation rising to a maximum just before the start of the next cycle an equal number of studies

6 demonstrate no change in RMR during menses. This most likely indicates that the menstrual cycle does have an effect on the RMR for some women and has no effect on others. These conclusions were confirmed most recently in a 2003 study in the British Journal of Nutrition. While we are still unsure how to distinguish those women whose RMR is affected by their menstrual cycle, it may be wise to increase your activity level one week prior to the onset of your cycle to compensate for a possible decrease in RMR. If nothing else, you will be practicing a healthier lifestyle and releasing endorphins that has shown to be deficient in those suffering from pre-menstrual syndrome. 13. Hydrate before you exercise to get the most out of your workout The goal here is to make sure your body has a balanced amount of electrolytes and fluid to carry you through your workout. For if you are dehydrated, recent guidelines provided by the American College of Sports Medicine in 2007 states that dehydration increases physiologic strain and perceived effort to perform the same exercise task. To appropriately maintain hydration, it is recommended that an average 70kg male consume 12-16oz of water approximately four hours prior to exercising. If you do not urinate or your urine is dark, then consume another 7-12oz of water two hours prior to exercising. The importance of hydrating several hours before you exercise is to provide sufficient time for fluid absorption and to allow urine output to return to normal so you won t have to run to the restroom during your exercise routine. Hyperhydration has not been demonstrated to provide a clear physiologic or performance advantage and in fact may harm you by causing a state of hyponatremia which in some rare cases can lead to hospitalization or death. 14. Maximize a healthy diet by not timing your dinner to TV shows A 2007 study in the Journal of Nutrition and Educational Behavior confirmed that eating in front of the TV as opposed to family type meals had a negative impact on dietary intake in adolescents that has been found to transcend to adults in other studies as well. This is believed to be due to the abundance of advertisements on TV promoting unhealthy food and particular soft drinks. By eating as a family without the TV on, adults can pass on healthy eating habits to their children by having a greater influence on what they are consuming. 15. Protein before or after a weight-lifting session

7 Long debated, much of the research points to having your protein load after your workout with the weights. Protein synthesis to create more muscle is increased after a session of weight-lifting provided the stimulus is of sufficient intensity. This transient increase is marked, but has a time span of approximately 48 hours. However, the closer you get to the 48 hour mark, the less amount of protein is synthesized. Thus as protein administration is crucial for an optimal effect on muscle building, an early intake of protein after exercise is recommended. 16. Is there a best time to take my cholesterol lowering medications? It is known that there exists a circadian variation in cholesterol and triglyceride levels in our bloodstream. Scientific studies have demonstrated that both cholesterol and triglyceride levels are predictably highest at the end of our active hours and the lowest are upon awakening. A recent study in the American Journal of Hypertension confirmed that of those patients taking their statin medication at night, 36.3% had control of their lipid values. This number was reduced to 20% when patients took their statins at midday. Patients were also more compliant in taking their statin (87.7%) at nighttime as compared to midday (78.6%).