Finnish engineer. Invented the wireless heart rate monitor 1977 — first commercial product to deliver real-time HR to athletes via chest strap. Founded Polar Electro 1977 in Oulu, Finland. Polar dominated wearable HR market for 30 years before Garmin / Apple consolidation. Still gold standard for accuracy among coaches and exercise scientists. Polar Vantage V3 (2024) reflects the hybrid sport + health watch trend.