Hi Great question. Remember machines are not 100% perfect, especially commercial gym machines, which are not medical machines. What I’d recommend is before any exercise take the client pulse and see what type of heart rate you are getting.
If you decide to put him on the machine again, see what the readings are saying. Once the HR gets up there, have the client come off and manual take his pulse or HR with a stethoscope (you could also use a pulse ox reader). Those methods will be much more accurate. At 72, a HR of 160 is very high. So I think those machines are giving you false readings.
Lastly, remember clients who are on beta blockers or have a history of heart issues and or high blood pressure you should not use target HR training with them. Blood pressure meds tend to slow pulse down.
Lastly, it’s maybe just me but I’d not put a 72 year old clients on a Stair-climber. Granted I don’t know your client. But I have several clients who are into their 70s, some very active but it’s not something I’d personally do with them.
Personal Trainer & Registered Nurse
Owner of Repke Fitness located in Severna Park/Millersville