Question: My workouts consist of a weight lifting session and then 30 minutes on the treadmill. My trainer suggests that leat spaghetti or potatoes soon after
I train. Is this a good meat, or is it too heavy?
Answer: Unless you hate those foods, your trainer's suggestion is a good one. Spaghetti and potatoes are excellent sources of complex carbohydrates at any time,
but there's a significant benefit to eating them within two hours after your cardio workout-more of the calories will be stored as sugar instead of fat in your
body. Dietary fat is usually eaten in the form of triglycerides, which are broken down into free fatty acids that can be taken up by tissues and stored again as
triglycerides. The important point is that fat can only be stored as fat; it doesn't turn into carbohydrate or protein. Carbohydrate, however, breaks down into
components that can be stored as either carbohydrate or fat. Both are used as an energy source, but carbohydrate is the preferred storage form for athletes.
The reason that eating complex carbs soon after aerobic exercise helps to facilitate carbohydrate storage is due to the actions of insulin, a hormone that
stimulates fuel storage in the body. Endurance activities like running and biking stimulate the body's tissues to be more sensitive to the effects of insulin,
and that leads to more efficient fuel storage, with more of the carb stored as sugar in the muscle tissues instead of fat in the adipose tissues.
I started a running program in conjunction with my weight training 21/2 months ago, and since then my resting heart rate hers decreased. Is that good?
Yes, it's very good. A lower resting heart rate simply means that your heart is delivering blood and nutrients to the body's organs and tissues more
efficiently, which means that it doesn't have to work as hard to perform the same task. A lower resting heart rate is an adaptation to endurance exercises that
involves both the sympathetic and parasympathetic branches of the nervous system.
The sympathetic nervous system is responsible for the impulse for "fight or flight." When stimulated by the brain, this system releases two substances, epinephrine
and norephinephrine, which are collectively called catecholamines and which facilitate certain processes that cause the heart to beat faster. The parasympathetic
nervous system, on the other hand, is associated with relaxation and a slower heart beat. A hormone called acetylcholine is the agent here-when released, it engenders
a relaxed state and retards the heart beat.
Together, the sympathetic and parasympathetic nervous systems modulate your heart rate. The physiological adaptations that occur when you do continuous aerobic exercise
like running, stair-stepping, biking, swimming or endurance rowing include changing the amount of catecholamines and hormones released, which ultimately affects your
heart rate. Regular endurance exercise increases parasympathetic activity and decreases sympathetic discharge. That means more acetylcholine and less catecholamine
released, the combined effect of which is a lower resting heart rate.
I've heard many different recommendations on fiber in the diet. Should I worry about fiber?
Many physicians and dietitians recommend increasing your intake of soluble fiber, the type of fiber found in oatmeal, oat bran, beans, vegetables and fruits,
because eating a diet rich in these foods can significantly lower serum cholesterol levels. It's believed that when these fibrous foods enter the small intestine, they
bind to cholesterol and carry it into the colon for elimination. Soluble fiber also binds to bile acids which are secreted by the liver to help in fat absorption.
Since the fiber binds to and later eliminates these bile acids, the liver takes cholesterol out of the bloodstream to produce new ones. A possible net effect is a lowering
of serum cholesterol levels. Consult a registered dietitian before starting a diet high in soluble fiber. Experts currently caution against eating more than 35 grams of
soluble fiber a day. Although it can lower serum cholesterol levels, it can also bind to important vitamins and minerals on its journey through your body.
When eliminated, soluble fiber takes everything with k-the cholesterol, bile acids, vitamins and minerals-so be aware that in this case too much of a good thing can have a
negative effect on vitamin and mineral absorption.