I agree with one exception- heart rate. Not that I agree with the very low heart rate of "fit" people of 40, but heart rate being high isn't a reliable metric either.
If everyone has the same heart pumping efficiency, sure, heart rate would be a good measure of metabolism. But that isn't the case. So, one could have a higher metabolism and have a lower heart rate than the next guy with a higher heart rate because his heart is more efficient at pumping blood.
Heart rate merely measures the rate at which the heart pumps, but doesn't take into account the amount of volume of blood pumped with each pumping cycle. The higher the volume pumped in each cycle, the more efficient the heart pumps.
The flow of blood in our body isn't all due to the heart pumping. The heart can be considered as a booster pump, where there is an existing flow that is not enough by itself to feed blood all around the body, and needs the heart to add additional pressure to boost the flow all around the body. This is as I understand it to be, and I would welcome any correction to this.
With this in mind, there is a metric that can be used that would measure the percentage of flow that is generated by the heart. This ranges from slightly above zero for a very weak heart to 20% for a very healthy heart. This metric is called the perfusion index (PI). The flow generated from the heart is called the pulsatile flow, where pulsatile comes from the world pulse, which would signify the flow coming from the beating of the heart, or the heartbeat.
Until last year, it was hard to measure the PI without spending a lot for it. Now, one can buy a pulse oximeter that has this feature for a little over $20. I've been using it for half a year now, in place of using heart rate as my metric. For me, it is a quantitative equivalent of a qualitative tool used by herbal doctors such as TCM doctors and western herbal doctors, where they feel a patient's pulse to see how strong or weak it is, how fast or slow it is, and how regular the strength or rate is.
I think it is a superior metric. I started out last year with a PI that ranges from 5 to 8. This year, the range is from 8 to 12, as a result of some improvements I've made with approaching my high blood pressure. I'm not so sure if this is the way to go in getting an objective measure of metabolism, as I couldn't get anyone in RPF to break out of their mould (did I say an a PI-enabled oximeter costs a little over $20") in using PI instead of heart rate, such that what I say is my own n =1. But I am pretty sure heart rate as a metric is not reliable. Even for me alone, I could not see an increase in heart rate as indicating with certainty an increase in metabolic rate. What more if I were to compare my metabolism with someone else.
But with PI, maybe I could do that. As what more could determine metabolic capability than knowing how much your heart is contributing to the total flow of blood, as the more the heart's contribution the more likely more nutrients, especially sugar and oxygen, is being supplied to the body for metabolism.
If everyone has the same heart pumping efficiency, sure, heart rate would be a good measure of metabolism. But that isn't the case. So, one could have a higher metabolism and have a lower heart rate than the next guy with a higher heart rate because his heart is more efficient at pumping blood.
Heart rate merely measures the rate at which the heart pumps, but doesn't take into account the amount of volume of blood pumped with each pumping cycle. The higher the volume pumped in each cycle, the more efficient the heart pumps.
The flow of blood in our body isn't all due to the heart pumping. The heart can be considered as a booster pump, where there is an existing flow that is not enough by itself to feed blood all around the body, and needs the heart to add additional pressure to boost the flow all around the body. This is as I understand it to be, and I would welcome any correction to this.
With this in mind, there is a metric that can be used that would measure the percentage of flow that is generated by the heart. This ranges from slightly above zero for a very weak heart to 20% for a very healthy heart. This metric is called the perfusion index (PI). The flow generated from the heart is called the pulsatile flow, where pulsatile comes from the world pulse, which would signify the flow coming from the beating of the heart, or the heartbeat.
Until last year, it was hard to measure the PI without spending a lot for it. Now, one can buy a pulse oximeter that has this feature for a little over $20. I've been using it for half a year now, in place of using heart rate as my metric. For me, it is a quantitative equivalent of a qualitative tool used by herbal doctors such as TCM doctors and western herbal doctors, where they feel a patient's pulse to see how strong or weak it is, how fast or slow it is, and how regular the strength or rate is.
I think it is a superior metric. I started out last year with a PI that ranges from 5 to 8. This year, the range is from 8 to 12, as a result of some improvements I've made with approaching my high blood pressure. I'm not so sure if this is the way to go in getting an objective measure of metabolism, as I couldn't get anyone in RPF to break out of their mould (did I say an a PI-enabled oximeter costs a little over $20") in using PI instead of heart rate, such that what I say is my own n =1. But I am pretty sure heart rate as a metric is not reliable. Even for me alone, I could not see an increase in heart rate as indicating with certainty an increase in metabolic rate. What more if I were to compare my metabolism with someone else.
But with PI, maybe I could do that. As what more could determine metabolic capability than knowing how much your heart is contributing to the total flow of blood, as the more the heart's contribution the more likely more nutrients, especially sugar and oxygen, is being supplied to the body for metabolism.