A good running top should have certain key features such as lightweight, moisture wicking fabrics, frictionless seams, appropriate fit and cut plus extra panels in key areas for extra ventilation or warmth.
The more money you spend on a running top then the more of these features you can expect to see . And like with all our advice, you will understand that the more running you do the more important these become.
As a general rule a short sleeve running top is an essential addition to your running wardrobe. These are perfect in their own right but can then be worn over a base layer or under a long sleeve top or jacket.
Base layers fit closer and next to the skin and are normally made from softer fabrics. They are especially important in the colder months when the maximum possible moisture wicking all over the body needs to be attained.
Long sleeve running tops are a simple extension to the short sleeve option but offer additional warmth in the arms for when the weather is a little colder. Some long sleeve running tops do have additional features such as finger loops.
Other things to consider are the style of neck you prefer because yet again there is lots of choice. The main options are round necks, v-necks, half-zips and roll necks.