Social media, including blogs, are popular conduits of exercise information that may influence the reader's thoughts and behaviours. It is unknown however, how bloggers represent themselves online, if they are qualified to give exercise advice, and what types of information they most commonly share on their blogs. This may cause confusion for readers and has the potential to contribute to misinformation, or unhealthy behaviours (e.g., exercise addiction). The current study used quantitative content analysis to examine the features of 194 popular fitness and exercise blogs, with a focus on blog authors. Additionally, 722 content pages from the blogs were analyzed for content type, post format, and interactive features. Results suggest that only 16.4% of bloggers report having fitness/exercise certifications although 57% report being a fitness/exercise professional. In addition to fitness/exercise, blog posts included content about related topics such as nutrition, and unrelated topics like fashion and politics. Blogs were highly interactive with 76.3% including comments sections. Most blogs included multimediality for content sharing with Facebook (90.7%), Twitter (86.1%), and Instagram (68.0%) most predominant. Blogs may provide an online space for like-minded exercisers to connect, foster a community of support, and learn more about various exercise modalities and facilities. Yet given the ambiguity of authorship, consumers may be left unaware if fitness and exercise bloggers are exercise experts, and whether or not blog content is a reliable source of exercise information.