U.S. researchers found the benefits of exercise for weight loss could be increased by using rapid -- or explosive -- muscle contractions. Scott Mazzetti, of Salisbury University in Maryland and researchers from Anderson and Ball State universities, compar...

U.S. researchers found the benefits of exercise for weight loss could be increased by using rapid -- or explosive -- muscle contractions.

DEAR DR. DONOHUE: Why have I lost so much weight? I dropped from 190 pounds to 165. I worked out three or four times a week, and I took three amino acids. Could the amino acids have caused the weight loss? Don't they build muscle?

DEAR DR. DONOHUE: Why have I lost so much weight? I dropped from 190 pounds to 165. I worked out three or four times a week, and I took three amino acids. Could the amino acids have caused the weight loss? Don't they build muscle?

DEAR DR. DONOHUE: Why have I lost so much weight? I dropped from 190 pounds to 165. I worked out three or four times a week, and I took three amino acids. Could the amino acids have caused the weight loss? Don't they build muscle?

DEAR DR. DONOHUE: Why have I lost so much weight? I dropped from 190 pounds to 165. I worked out three or four times a week, and I took three amino acids. Could the amino acids have caused the weight loss? Don't they build muscle?

DEAR DR. DONOHUE: Why have I lost so much weight? I dropped from 190 pounds to 165. I worked out three or four times a week, and I took three amino acids. Could the amino acids have caused the weight loss? Don't they build muscle?

DEAR DR. DONOHUE: Why have I lost so much weight? I dropped from 190 pounds to 165. I worked out three or four times a week, and I took three amino acids. Could the amino acids have caused the weight loss? Don't they build muscle?

Geri Halliwell's friends are concerned about her recent weight loss, according to a report.

Geri Halliwell's friends are concerned about her recent weight loss, according to a report.