Compression garments are popular with some athletes, such as runners and basketball players, who think the tight-fitting clothing lends a competitive edge. But that may not be the case, according to two new studies presented Thursday at the annual meeting of the American College of Sports Medicine being held in Baltimore.

One study looked at the effect on oxygen consumption among 16 trained male distance runners who wore lower leg compression sleeves. The sleeves, socks that run from just above the ankle to just below the knee, were worn by the runners during a 12-minute running test. The athletes also did the test without the sleeves.

Oxygen consumption did not change significantly in either test. However, small variations were noted — four runners had greater than 1 percent average increase in oxygen consumption, which means they ran less efficiently. Four runners also had a greater than 1 percent average decrease in oxygen consumption. There was no change in running mechanics.

Abigail Laymon, the study’s lead author and a researcher in the department of kinesiology at Indiana University, also gave the athletes a questionnaire asking their feelings about the compression sleeves. Those who had better outcomes with were more likely to have a favorable attitude about the garments and thought their racing would improve while wearing them.

“Overall, with these compressive sleeves and the level of compression that they exert, they don’t seem to really do much,” Laymon said in a news release. “However, there may be a psychological component to compression’s effects. Maybe if you have this positive feeling about it and you like them then it may work for you. It is a very individual response.”

The other study focused on upper thigh compression garments. Researcher and lead author Nathan Eckert, a human performance doctoral student in the department of kinesiology at Indiana University, tested three types of compression garments on 25 men who did vertical jumps. Each test subject did the jumps while wearing a waist-to-knee garment that fit exactly, one that was a size smaller, and one that was a size larger.

No differences were noted in jump height. “We looked at various different angles to see if the variability changed and nothing significant happened,” Eckert said in a news release. “This basically states that at all three different levels of compression did absolutely nothing for them.”