Update README.md

README.md

@@ -23,8 +23,8 @@ It is the largest dataset for developing and evaluating wearable heart-rate dete
 
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-- **Participants, Duration & Ground truth:**  
-  16 healthy adults; 810 min (~13.5 h) each, 216 h total. Ground truth: obtained from ECG with Pan–Tompkins and cleaned further during motions.
+- **Participants, Duration & Ground truth for heart rate estimation:**  
+  16 healthy adults; 810 min (~13.5 h) each, 216 h total. Ground truth heart rate: obtained from ECG with Pan–Tompkins and cleaned further during motions.
 
 - **Modalities & Placements:**  
   PPG, ECG (Lead I), 3-axis accel, skin temp, barometric altitude