Washington, March 20 : The efficiency of human running varies with speed, and each individual has an optimal pace at which he or she can cover the greatest distance with the least effort, according to a study.

Karen Steudel, a zoology professor at the University of Wisconsin-Madison, says that the finding debunks the long-standing view that the energy needed to run a given distance is the same whether sprinting or jogging.

Though sprinting feels more demanding in the short term, the longer time and continued exertion required to cover a set distance at a slower pace are thought to balance out the difference in metabolic cost.

Washington, Mar 20 : Revolutionary new drugs that could stop Alzheimer''s disease in its tracks are being tested by scientists.

Professor Simon Lovestone, of the Institute of Psychiatry at King's College London, told the annual meeting of the Alzheimer's Research Trust that the drugs are undergoing clinical trials.

Current treatment can help only to reduce symptoms but cannot prevent the disease from destroying brain cells.

The results from trials of up to 11 new medicines should be known within one to three years.

Washington, Mar. 20 : President Barack Obama has attracted controversy again by saying that his poor bowling skills make him a likely candidate for the Special Olympics.

His spokesman, however, quickly said Obama did not mean any offense by his comment.

According to Politico, the late-night turn is a political risk for a president overseeing a recession.

Washington, Mar. 20 : While Pakistan has raised serious concern over media reports about a possible extension of US drone attacks in Baluchihstan, US Defence Secretary Robert Gates has denied that such a plan is being charted out by the Obama administration.

Addressing a regular Pentagon press briefing, Gates rejected media reports that said Washington is worried about the activities of the Quetta shura in Balochistan.

Washington, Mar 20 : Scientists have moved a step closer to developing a drug that could actually stop the progress of Alzheimer''s disease.

They have identified a molecule that can form the basis for a new therapy for the neurodegenerative disease.

A typical characteristic of the brains of Alzheimer''s patients is the presence of amyloid plaques, which are abnormal accumulations of the c¬-amyloid protein between the neurons. The sticky c¬-amyloid arises when the amyloid precursor protein is cut into pieces incorrectly.