Actually, I disagree.
162 is quite a high heart rate, and indicates quite an intense workout. Working out at that intensity will typically burn 600-800 calories per hour, so 312 sounds about right.
140 calories burned sounds much too little for that kind of heart rate.
One thing you may want to check is the weight settings on your HRM, whether you have entered your current weight correctly, and also the units of measure (pounds versus kilograms). My suspicion is that this is what the issue is. 1 kg = 2.2 lbs, and 140 x 2.2 = 308, which is almost exactly what the online calculators are telling you.
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.
| current weight: 178.0