1. The standard age derived method which is MHR = 220 - age (for me 220 - 51 = 169). 2. The Ball State University Method Regarded as more accurate for the youngest and 'older' people: For Men MHR = 214 - (0.8 * age) For Women MHR = 209 - (0.7 * age)
The following graph indicates the discrepancy between the two methods:
Each zone has a lower and upper Training Heart Rate (THR) - repeated here.
Moderate Training Zone = 50 - 60% of MHR Weight Management Zone = 60 - 70% of MHR Aerobic Training Zone = 70 - 80% of MHR Anaerobic Training Zone = 80 - 90% of MHR Red Line Training Zone = 90 - 100% of MHR I include three methods of calculating the limits of the zones. For each of these the work rate ratio is the percentage divided by 100 i.e. For 50% use 0.5, for 60% use 0.6 etc repeat the sum up to 90%. 1. Max HR method - Multiply MHR by the work rate ratio. THR = MHR * Work Rate Ratio. 2. The Karvonen method that uses one's Resting Heart Rate. a) Calculate Heart Rate Reserve; HRR = MHR - RHR and use this in the formula b) THR = RHR + (HRR * work rate ratio) 3. My adjusted Karvonen method that reduces the RHR by multiplying it by 0.7; this gives results between the other two methods. a) Calculate Adjusted Rest Heart Rate; ARHR = RHR * 0.7 b) Calculate Heart Rate Reserve; HRR = MHR - ARHR and use this in the formula c) THR = ARHR + (HRR * work rate ratio)
You don't need to do these sums - go to The Calculators.
The following graph indicates the discrepancy between the three methods:
The area around 50% to 60% of effort is the practical range where the difference is most noticeable.