The Jabra Elite Active 45e is a fantastic choice for fitness and sports enthusiasts looking for secure and comfortable wireless earbuds under $100. These earbuds feature a unique earhook design that ensures a secure fit during intense workouts and sports activities. The IP67-rated waterproof and sweatproof design makes them perfect for outdoor use and gym sessions. With up to 9 hours of battery life, you can enjoy your favorite tunes during long workouts without worrying about charging. The Jabra Elite Active 45e also offers excellent sound quality and noise isolation, allowing you to stay focused on your workout. The built-in microphone and one-touch access to voice assistants like Siri and Google Assistant make it easy to stay connected on the go. However, the bass response may not be as powerful as some users might prefer, but overall, the Jabra Elite Active 45e offers a great balance of features, comfort, and performance for fitness and sports enthusiasts.

The Plantronics BackBeat FIT 350 is an excellent choice for fitness enthusiasts who need a lightweight and stable pair of in-ear headphones for running and gym workouts. These headphones feature a secure-fit earloop design that ensures they stay in place during intense activities, and the ultra-lightweight construction makes them comfortable to wear for extended periods. The 6mm drivers deliver powerful audio with deep bass, and the noise-isolating eartips help block out distractions, allowing you to focus on your workout. The BackBeat FIT 350 is also sweatproof and water-resistant, making them suitable for use in various weather conditions and during sweaty workouts. The inline controls allow you to easily adjust volume, skip tracks, and take calls without reaching for your device. However, the battery life of up to six hours may not be sufficient for all-day use or long training sessions. Despite this, the Plantronics BackBeat FIT 350 offers a great combination of comfort, stability, and sound quality at an affordable price.

The Sony MDR-XB510AS is a great choice for fitness and sports enthusiasts who want powerful bass and a splashproof design. These in-ear headphones feature Sony's Extra Bass technology, which enhances low-frequency sounds for a more immersive listening experience during workouts. The headphones are also IPX5-rated for water resistance, making them suitable for use in light rain or during sweaty workouts. The secure fit and comfortable silicone earbuds ensure that the headphones stay in place during intense activities, while the built-in microphone and inline remote allow for easy hands-free calling and music control. However, the Sony MDR-XB510AS may not be the best choice for those who prefer a more balanced sound profile, as the emphasis on bass can sometimes overpower other frequencies. Additionally, the in-ear design may not be suitable for everyone's comfort preferences. Overall, the Sony MDR-XB510AS offers a powerful bass experience and a durable design for fitness and sports enthusiasts on a budget.