The Sennheiser Momentum Sport are great exercise earbuds with some major flaws

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Hybrid wearables are nothing new in the audio space. Headphone brands like Amazfit, Jabra and Soul have created wireless earbuds that double as activity trackers, but none of them have bridged the gap successfully. Sennheiser thinks it can. Otherwise, it wouldn’t have launched their first-ever workout earbuds with fitness monitoring: the Momentum Sport.

The legacy audio staple partnered with Polar to develop a body temperature sensor and a photoplethysmography (PPG) heart rate sensor that outputs data to some of the best workout apps. These buds are also stacked with high-end features and share similar sound traits to the flagship Momentum True Wireless 4, which are some of the best true wireless earbuds for audiophiles.

What’s on paper mostly sticks, specifically active noise cancellation and audio. Where the Momentum Sport heavily stumble are activity tracking and charging — two weaknesses that don’t exactly justify their expensive $330 price tag.

Sennheiser Momentum Sport

Offering elite sound and noise cancellation in a sporty design, the Momentum Sport buds optimize workouts with minimal interruptions while allowing users to gauge their daily activity.

What we liked about them

Vibrant sound that complements versatile ANC

Sennheiser’s all-new 10mm TrueResponse transducer delivers robust bass right out of the box. I enjoyed lively, emphatic sound that didn’t waver when switching from contemporary to traditional music genres.

Kendrick Lamar’s “DNA” fueled my energy tank before a 5K run. The snarling 808s produced lengthy reverberation that kept adrenaline flowing throughout the listen, while the rapper’s fiery rhymes sounded prominent over the boomy production. System of a Down’s “B.Y.O.B.” moved my workout along with a blistering combination of electrifying drum hits and thrashing riffs. Jazz classics like Ahmad Jamal Trio’s “Dolphin Dance” were perfect for recovery and exhibited superb frequency range, feeding my ears mellow double bass and smooth hi-hats.

Numerous sound-enhancing features are available, including a customizable 5-band EQ with multiple presets, Sound Check for automatically creating a sound profile tailored to your hearing and Sound Zones to fine tune audio based on your location. My Sound Check profile emphasized bass and mids. The Bass Boost toggle in the EQ setting increased the low end, but the effect was excessive on select EDM and hard rock tracks. Qualcomm’s aptX Adaptive codec dynamically scaled bitrate for greater clarity.

ANC neutralized incidental sounds very well. Heavy machinery and talkative exercisers were muted every time I worked out at the gym. Common household distractions (e.g., kitchen appliances, loud TVs) never broke my concentration, though my toddler’s screams were audible from another room. I wore the buds outside on several occasions and was rewarded with peaceful listening for the most part. Only blaring noises like sirens and whistles entered the soundstage. The Anti-Wind mode granted satisfactory wind resistance. Transparency mode came in handy for increasing situational awareness. Sennheiser’s mic array captured ambient noise and vocals at a high level.

Call quality was just as impressive. Voices sounded loud and clear on both ends. Background noise was apparent during outdoor chats, but clients and friends managed to hear me over the fracas.

The most feature-filled sports buds ever

I thought the Beats Fit Pro and Jabra Elite 8 Active were big on extended functionality. The Momentum Sport are even more high performance. Most of Sennheiser’s top features are programmed into the buds, along with a few exclusive perks. Audio purists can tweak what they hear by enabling ANC, aptX Adaptive, EQ, Sound Check/Zones or Transparency mode. There’s a dedicated tile that displays your body temperature and heart rate. Controls can be assigned and customized on the homepage. More features are hidden in the Settings page, including two battery-saving modes, wear detection and an Auto-Accept Call function to accept calls when removing the buds from the case.

Outside of the app are premium wireless features such as Bluetooth 5.2 and multipoint technology to pair the buds with two devices simultaneously. Connectivity is stable during calls and music streaming. Range extends to 60 feet.

Sleek and sporty

Sennheiser did a standup job constructing the Momentum Sport, at least when it comes to the buds. They exemplify the brand’s clean and sophisticated aesthetic and come with robust protection. The outer shell is made of sturdy plastic and has an IP55 rating for dust and water resistance. You can put the buds through months of intense exercising and not worry about them malfunctioning or looking decrepit. Their oval design is bigger than other similarly shaped rivals, but it isn’t cumbersome. Multiple-sized fins and tips are bundled to properly fit different ear shapes, and there’s a Fit Test in the app to determine the best fit and seal option.

The charging case is compact, lightweight and slim for convenient portability. IP54 certification keeps it dust and water-resistant. On the front is a flap that covers the USB-C port. However, there are some design issues (more on that later).

What we didn’t like about them

Disappointing battery life

The Momentum Sport are rated at 6 hours per charge. That’s the industry standard for most noise-canceling earbuds. Playtimes drop drastically when factoring in ANC, fitness tracking, multipoint and Sound Zones. Turning on the Battery Eco and Battery-Protect didn’t preserve much juice. I got about 4.5 hours of use before recharging. The wireless charging case only holds up to 24 hours. A 10-minute quick charge nets you 1 hour of listening time (with ANC on).

Meanwhile, the Elite 8 Active and Fit Pro offer several hours more playtime, stronger charging and superior battery management.

Inadequate fitness integration

These buds aren’t replacing your Apple Watch or the best fitness trackers, due to their inaccurate heart-rate monitoring. I compared my beats per minute (BPM) in the Sennheiser Smart Control app to what the treadmill registered — the latter provided more precise readings. On the plus side, my body temperature was usually correct.

It’s nice that Polar opened its ecosystem to support the Momentum Sport. Unfortunately, the brand experience is tame unless you download the Polar Flow app and own a Polar wearable. Momentum Sport users will only be able to read and store their body temp and heart rate readings on the Polar Flow app.

Flimsy charging case

The lid ruins the charging case. It flops around and the magnetic closure is weak. I tested lockability by dropping the case on different surfaces and the buds fell out multiple times. Even worse is the bundled lanyard that feels chintzy and can easily snap if tugged on too hard.

Bottom line

The Sennheiser Momentum Sport’s excellent sound, substantial noise cancellation and terrific fit make them an ideal workout companion for all environments. Personalized features like Bass Boost and Transparency Mode help cultivate intense workouts.

I give credit to Sennheiser for trying something new with its fitness tracking initiative, but the feature isn’t as reliable as it is on advanced wearables. What’s more concerning is the low battery life and unsecure charging case, which hurt their purchasability. Then again, $330 is too expensive for any pair of sports buds.

If you’re a brand enthusiast that wants hallmark sound in a Sennheiser package, then the Momentum Sport will appease your audio and exercise needs. You just have to accept their glaring flaws.

Note: The prices above reflect the retailers' listed price at the time of publication.

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