Changes

There are various formulas for calculating HR_max based on age. However these formulas are a statistical approximation, so the actual HR_max could vary significantly. An analogy would be estimating your weight from your height; you can get a value, but he could be out so far as to be worse than useless. The chart below shows how the measured HR_max varies with age. There is an obvious correlation, but you can also see the variation from the average. If we consider age 50, the average HR_max is 173A 2002 analysis concluded that '''"Currently, but there are people in the study with an actual HR_max that is as low as 158 and as high as 200. If a 50 year old athlete is aiming no acceptable method to work out at 75% of estimate HR_max, then the calculated HR_max would indicate that 130 BPM is the right intensity. If their actual HR_max is 158, then they are working out at 82% of HR_max, which is a lot higher. On the other hand, if their actual HR_max is 200, then they are working out at 65% of HR_max which is too low. This means that the calculated HR_max should be used with caution.[[File:HRmaxAge.jpg|none|thumb|300px|Maximum heart rate against age"'''<ref name="MaxCalcsurp"/>.]]

{| class="wikitable"!'''Age'''!!HR_max!!'''Age'''!!HR_max!!'''Age'''!!HR_max!!'''Age'''!!HR_max!!'''Age'''!!HR_max!!'''Age'''!!HR_max!!'''Age'''!!HR_max|-valign="top"|'''20'''[[File:HRmaxAge.jpg|none|194thumb|400px|'''30'''||187||'''40'''||180||'''50'''||173||'''60'''||166||'''70'''||159||'''80'''||152Maximum heart rate against age<ref name="MaxCalc"/>.]]|-[[File:MaxHR2.jpg|'''21'''none|thumb|193400px||'''31'''||186||'''41'''||179||'''51'''||172||'''61'''||165||'''71'''||158||'''81'''||151|-|'''22'''||193||'''32'''||186||'''42'''||179||'''52'''||172||'''62'''||165||'''72'''||158||'''82'''||151|-Data of HRmax for 225 subjects, 4 to 33 years<ref name="surp"/>.]]|'''23'''[[File:MaxHR3.jpg|none|192thumb|400px|'''A subset of this the data for ages 11 to 33'''||185||'''43'''||178||'''53'''||171||'''63'''||164||'''73'''||157||'''83'''||150|-|'''24'''||191||'''34'''||184||'''44'''||177||'''54'''||170||'''64'''||163||'''74'''||156||'''84'''||149|-|'''25'''||191||'''35'''||184||'''45'''||177||'''55'''||170||'''65'''||163||'''75'''||156||'''85'''||149|-|'''26'''||190||'''36'''||183||'''46'''||176||'''56'''||169||'''66'''||162||'''76'''||155||'''86'''||148|-|'''27'''||189||'''37'''||182||'''47'''||175||'''57'''||168||'''67'''||161||'''77'''||154||'''87'''||147|-|'''28'''||188||'''38'''||181||'''48'''||174||'''58'''||167||'''68'''||160||'''78'''||153||'''88'''||146|-|'''29'''||188||'''39'''||181||'''49'''||174||'''59'''||167||'''69'''||160||'''79'''||153||'''89'''||146|-years, n=196<ref name="surp"/>.]]