Started intermittent fasting (8 hours eating, 16 hours not) 5 days ago and noticed my average heart rate during my zone 2 sessions on the treadmill has slightly suffered. My heart rate is 5bpm higher consistently than where it was previous to 5 days ago. Not a huge difference, but something I noticed. Nothing else changed. Same level of calories and same food.
Anyone else notice something like this during intermittent fasting?
I don’t measure my heart rate but I know I can feel a bit jittery when fasting or right after breaking my fast. However I apparently also have issues with insulin resistance (and taking meds for that). So I’m wondering if it could be a similar issue? I mean who knows, maybe it’s normal, i don’t know. Just throwing ideas out there.
I have been IF for over 3 years now and I haven’t noticed any change in my overall heart rate and I exercise 5 days a week in the gym and swim. I did cut down on my cardio, but that was because I didn’t want to sprint for interval training as I didn’t want to stuff my knees up at my age
My resting heart rate is in the low 40s after getting to my goal weight. My cardio is better than it was when I was in my late 20s and I am 47 now. I run now and haven’t really done that in almost 20 years. I usually do my hard cardio session in the morning while still fasting. I still do 16:8 but am not in a deficit now. I have zero problem doing that. So maybe pull back the hard cardio if you are in a deficit to lose weight. Weight loss is really just consumption control anyways. You want to lose 10 pounds of fat then you don’t really need to exercise to do that. That happens because your diet allows that to happen. I worked out hard for 20 years and didn’t have visible abs until I learned this. And the abs happened at an age where they aren’t supposed to happen. It happened because that is much more about long term diet than the workout you do. Understand that any change like this the body needs to shift to accommodate and that takes time. And to me long term is thinking in term of months and years not days and weeks. But as others are telling you make sure your water/electrolytes intake is good.
Also do you drink alcohol? Alcohol consumption can also increase your resting heart rates ways.