Many of the liquid, effervescent and chewable forms of creatine on the market may be ineffective and of poor quality, suggests recent tests of a sample of the performance-enhancing products by ConsumerLab.com.
Tests on a sample of 22 muscle enhancing supplements found no problems among standard creatine powder products. However both liquid creatine products tested were of poor quality - one contained virtually no creatine and was contaminated with a creatine breakdown compound despite claiming to contain '100 per cent stable and 'pure' creatine and boasting 'builds lean muscle mass', reported ConsumerLab.
Creatine supplementation has been shown to be useful in maintaining strength in repetitive, brief, high-intensity sports activities. Its popularity among athletes has produced a flood of new product forms onto the market, increasing competition among creatine manufacturers but also raising quality concerns.
The other liquid product was also contaminated with creatinine and contained less than 95 per cent of its claimed creatine. Both products suggested unusually low doses of creatine (1,000 and 2,000 mg, respectively, rather than the standard 5,000 mg to 20,000 mg).
An effervescent product also failed tests for containing creatinine contamination and a chewable wafer product was found to contain less than 90 per cent of its claimed creatine.
"There are legitimate, pure creatine products on the market but there are also pure rip-offs," commented Tod Cooperman, president of ConsumerLab.com. "People considering muscle enhancement supplements should be realistic about the effectiveness of these products and skeptical about their contents - particularly with newer forms."
All HMB (hydroxy methylbutyrate) products tested in the review passed, except for one that had less than 90 per cent of ingredient, thought to help increase muscle mass and strength with weight training.
Glutamine supplements - not proven to boost exercise performance although it may reduce the incidence of infection in athletes who are over-training - contained their claimed amounts, but one failed to pass the review for not following FDA labeling regulations, featuring unapproved claims.