G-Shock has introduced the GBDH2000, their first watch with heart rate monitor. It also incorporates GPS to track your workout.
Casio describes the functions, “Using optical sensors to provide heart rate measurements, an accelerometer to count steps, and a gyroscope to improve swimming sessions, athletes can accurately monitor their training sessions.”
What’s more, it is rechargeable via USB or solar, the latter extending its use in the field.
Aside from the Black model with Red pop seen here but there is also a high viz Yellow band available as well as an Amazon exclusive murdered out version.