Essentials of Nutrition for Sports

How about: A study of height and caloric consumption found
that taller people eat more. If you conclude: To grow taller, eat more, a logic course will help you not only evaluate studies better, it will help you get through life.

Where Did You Get the Information?

Information from lay publications, advertising, fellow athletes,

endorsements, or coaches may be biased. Read more about this on page

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.

Published results of studies should not be taken at face value

alone. Peer-reviewed studies are of greater value than self-funded self-published studies. Abstracts or reports are of lower value.

Smell Test

Every study method and design has limitations. Irrespective of

the methods used, the results should make sense to you. If the author’s results do not make sense, be cautious about accepting them at face value.

Study Design

Suppose you have two treatments to compare. They might be

two diets, two forms of exercise, or two pieces of equipment. How should you design your study to obtain a valid comparison of the two treatments?

Common sense probably tells you, correctly, to give the

treatments to two groups of comparable subjects and see which group does better.

It is simple, yet it can be complicated. Give more weight to studies that are prospective, controlled,

double-blinded, and include large numbers of subjects.

Prospective, Double-Blinded, Randomized, Controlled Trials

Done well, these studies genera

lly provide a high level of

evidence.

This design reduces the effects of confounding and bias more

than other designs. Prospective

A study in which subjects are enrolled and then followed

forward in time. This is important

in studies on ergogenics, therapy,

prognosis, or harm. Retrospective studies make hidden biases likely. Blinded (Masked)

Blinded

means blind with respect to treatment.

In a

single-blind study

, subjects do not know what treatment they

are receiving. This insures their responses will not be affected by prior expectations and that subseque

nt behavior will not be affected

by knowledge of the treatment. In some rare instances,

single blind

refers to situations where subjects know their treatments and only the person evaluating them is blinded.

In a

double-blind study

, subjects and anyone who has contact

with them or makes judgments about them is blinded to the assignment of treatments. This insures subjective judgments will not be affected by knowledge of a subject’s treatment.

In

triple blinding

, the analyst or statistician is given the data with

uninformative treatment labels such as A and B and their identities are not revealed until the analyses are completed.

Blinding improves the quality of a study. For example: A

researcher studying bone density in cyclists and attempting to show that cyclists had low bone density

discarded the results of one cyclist

who had high bone density, after co

llecting her data, on the basis of

the subject having been an ex-runner. If this subject was to be excluded, she should have been ex

cluded before her bone density

results were known.

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