Studies have shown that music can increase your workout intensity and may even help relieve the pain of a strenuous run or workout. The trouble is, it’s difficult to find a good pair or earphones that a) stays put through the rigours of a run or energetic HIIT workout, and b), delivers high-quality sound. When it comes to in-ear workout earphones it can be hard to balance these two elements. Running with earphones or headphones that dislodge with every leap up a gutter up can spoil a good run. Yes, Apple, I’m talking to you. But good sound is paramount, too, as most people workout with a playlist at a volume just below OH&S mandated safe levels. Sennhieser have offered up their new CX Sport earphones that balances both pretty well.

Out of the box, the CX Sport looks pretty cool. They’re stylish and well-designed with nice little reflectors on the earpiece, a bonus for night runners. The CX Sport use little fins to lodge the buds into the shell-like ear, as many workout earphones do these days, primarily because it’s a good system if you can get the size right.earphones To achieve this, the CX come with three sets of ear fins for different size ear lobes and four sets of ear adapters for different size ear holes. If you invest a bit of time experimenting with the sizes for your ear, it’ll pay off big time, as the CX will stay firmly lodged when fitted correctly.

To give them a test, I went for a run-jump, a military inspired workout that combines a 5-kay run with incline push-ups, burpees, sit-ups and chin-ups. Before I went I attached the CX Sport’s small T-shirt clip that holds the wire connecting the earpieces to my shirt. I cranked up my favourite playlist and off I went. They stayed so firmly in place, that by the end of the run I was determined to see what activity would actually dislodge them. This saw me doing commando rolls and handstands in the local park, much to the amusement of a mum’s group nearby.

The CX Sport features Bluetooth 4.2, a robust version that delivered a strong connection. My phone stayed in my Salmon running pack and never once missed a beat despite bounding down a rough trail for half the run. I stopped and walked about 30 metres from my pack without losing the connection.

The buttons to control the device sound are big and easy to operate with a thumb, a problem I’ve had with other headphones with buttons built for people with Donald Trump sized hands.

The sound was impressive, with good clarity at the high end and mid registers. The bass was lacking a little for a head-banger like me, but that probably has more to do with my aging eardrums than the earphones.

Sennheiser claim that fully charged the CX Sport delivers six hours of playing time, which I never tested, and I doubt I ever would, even on a long Sunday ride. They do have a quick charge capability: put them on charge for 10 or 15 minutes and you’ll get an hour, which I did several times in the car on the way to the gym.

All up the Senheiser CX Sport and a very good pair of workout headphones. There’s cheaper out there, but earphones not something you want to skimp on. The last thing you want on a run, or worse, a ride, is earphones falling out and the CX Sport are designed to stay put. And they delivery a nice crisp sound. What more could you want, really? They retail for around $199.