A new study by Leiden University in the Netherlands has found that certain gut bacteria can improve muscle strength in mice. The study found that people with stronger muscles are more likely to harbor a particular species of bacteria in their guts, which when fed to mice, they became stronger. The researchers believe this microbe could be used as a probiotic supplement and potentially as a drug to treat frailty in the elderly. However, future clinical trials in humans will determine if this can safely enhance muscle strength. The findings were published in the journal journal The BMV.