Our Verdict 
Good fitting headphones for the gym. As for the sound, the bottom-end is nicely taut and punchy and they're dynamic and detailed
For 
Dynamic and detailed
fit well
Against 
There's a little roughness and they leak a bit of noise
Reviewed on

These Philips headphones claim to have ‘turbo bass', which sounds a bit silly, but we have to admit the bottom-end is nicely taut and punchy, and leads to an agile midrange and treble.

True, there's a little roughness at busy points and they leak a bit of noise, but these are dynamic and detailed, and they'll definitely stay on at the gym.