I little bit of my B12 history: diagnosed 7½ years ago, been self injecting for 7 years, and am currently SI'ing every 3 days. With this protocol I have no symptoms. I can walk for miles every day, I can do weight training at the gym 2 to 3 times a week, I work, I go out, I have a happy, healthy marriage, and life is good. However, whenever I try to incorporate some form of cardio exercise into my life I get a return of symptoms. I had it a few years ago when I tried Couch to 5k. I had to give up after 10 days because I got the tell-tale signs that the body wasn't happy. I've been doing fantastic for a year or so now so last week I bought myself a skipping rope, and thought I'd give that a go. I've only done a few minutes at a time for 4 out of the last 5 days, but I've now got the same tell-tale sign. For me, the first returning symptom I get is a numb, but not fully numb, right knee and right foot (weird, I know, but that's what I get lol). And this frustrates the heck out of me!! I just cannot ever seem to do any cardio exercise: well, anything of a higher intensity than walking. I know this happens to me, I just don't understand why it does, and why it happens so quickly. Surely my B12 levels are not depleting that quickly from that short burst of cardio?? It happened when I was SI'ing every day too. It baffles me, it really does!
After some info on cardio exercise an... - Pernicious Anaemi...
After some info on cardio exercise and B12 deficiency.......
I find that I have different energy levels all the time. It really puzzles me because it doesn't seem to relate to what I do during that day. One day I can go for a 5 mile walk and feel great and another day I am exhausted from the get go. I take the same amount of B12 on both types of days. I think I just have to accept that my old level of fitness is gone.
Hi Charks, thanks for your reply. As a general rule nowadays I am probably the most active I have ever been, what with my physical job, and going to the gym a couple of times a week. My energy levels are, for the most part, consistent daily, but the issue still seems to be more intense cardio exercise: running, skipping with a rope, cycling, etc. And it baffles me as to why I can be so active without issue, but then a few short bursts of intense cardio brings about the symptom that, for me, is the sign that I've done too much. I know it happens, and I accept that, but I would love to know what it is about higher intensity cardio that does it.
Hi BeachArt, just a speculation, but do you think those nerves were damaged long term by lack of B12? So are the first to react when you place higher demand on your body? Do you feel deficient in other ways after cardio? Not a scientist or medically qualified, just curious like you!
Myoldcat, I do often wonder about long term nerve damage. I had such severe neurological symptoms initially, but over the years of self treating they have disappeared. Even the numb right knee and foot rarely appear nowadays. But it is always the first sign I get when I've done higher intensity cardio. Surely if there was long term nerve damage I would feel it all the time? As for your other question, do I feel deficient in other ways after cardio: not initially, it happens a few days in. Yesterday for example, as well as the numb right knee and foot I felt tired, cold, and irritable.
I wonder whether 'front loading' with an extra injection could help? Flood your system with B12. Maybe as you've healed a lot and are now SI every 3 days rather than every day you might notice a difference? But how long before cardio, that would be the question... I don't do intense cardio, but sometimes do my jab a day earlier or sneak an extra one if I have a lot going on physically or mentally.
I always add extra jabs if I've done more, or going on holiday, etc. Honestly, it just seems to be cardio that my body has an issue with. It did it when I SI EOD, and now at every 3 days. I'd just love to know the science behind why it impacts me/us as it does.
I’m always curious about how exercise affects fellow sufferers so thank you for raising this. Your routine sounds great but I understand the frustration re cardio. My story is very similar to yours. I can generally manage walking, (although my limit is about 5 miles), pilates and some strength training ok if I pace myself carefully but any cardio wipes me out for several days afterwards. I feel great on the day that I do it then really shattered and hungover with a return of headaches, tinnitus and other symptoms which have otherwise abated since starting treatment (currently SI EOD) for 2-3 days afterwards. I’m never sure if it’s due to the PA or other issues (also have Hashimotos, endometriosis and diagnosis of fibromyalgia) but as an ex fitness instructor I don’t recognise myself. It doesn’t even seem to be about duration as even 10 minutes of cardio is enough to cause it. I mainly swim as I find the after effects are a bit less than other forms of cardio but only manage once a week and sometimes not at all - like charks I find my energy levels are inconsistent.
I’m sorry I can’t offer any answers but I’m just as baffled and curious.
Realtiger, thank you so much for your reply. It means a lot to know that I am not the only one. Not that I'd wish this on you lol, but to know that it's not just me does help. Like I said, with my SI protocol I am symptom free, for the most part. I can walk for miles with no payback, and I can go to the gym to do weight training 2 or 3 times a week without issue. But even a little bit of cardio still seems to affect me. I would dearly love to know the science behind it.
My pet theory, for what it’s worth, is that it’s connected to some kind of impairment to the energy producing pathways at cellular level meaning we reach our anaerobic threshold at a much lower level of intensity than others when doing cardio. I would love to be able to corroborate this. This has just reminded me of some advice I read here. I’ve never tried heart rate monitoring like this as I’m pretty sure this threshold isn’t consistent in my case but it could be worth a try
cfsselfhelp.org/library/pac...
That's really interesting - I used to do a fairly intense cardio class, and my heart rate would peak incredibly quickly, faster than others in the class. I stopped as I tended to feel awful afterwards for several hours, so it just wasn't worth it
I can so identify with this. Still feeling terrible after swimming for 30 mins on Sunday - total repeat of last time I tried returning to swimming back in April after starting treatment in January. This has been a long-standing issue for me but had high hopes of SI improving things. Wonder if we have to build up literally 5 minutes at a time over time to be able to sustain longer bouts of cardio.
I have a numb big toe today after taking my kids to the swimming pool this morning. I SI 3xdaily, and I'm noticing if eat something that I'm sensitive to I get major pain in my left foot and also need an extra dose for that to heal up. Baffles me too.
Like you excercise like walking and swimming are fine and I can do them for extended time, but hard physical work causes me to feel awful the next day. I assume it is post exercise fatigue but there is a definite intensity threshold which triggers it. The other trigger for the symptoms is driving more than five or so hours especially if I get dehydrated. Weirdly I find drinking full fat coke helpful in minimising the effect.
It is all very weird isn't it? I know it happens to us, I would just love to know the science behind it .
Hi BeachArt and all - for me…
Coming up to 20 months B12 PA SI treatment. I was a keen runner (long and mid distances), circuits, HIT. Have 4 kids. Lots of energy.
The reason I went to get checked out was that in Jan22 my shorter runs felt like long ones. And I felt every step was a challenge. And I started to have heel pain that stopped me exercising.
Started B12 loading etc, physio for 6 months, nerve damage was confirmed via nerve conduction tests. Advice I got in this group was to rest and slowly build up again.
So 20 months later I’ve been building up - gym HIT, martial arts and really much happier. This training gives me a bounce in my step.
But road cycling 20miles zaps my energy (not mountain biking). Running short distances are ok. Longer runs Zap me. So definitely there is a longer time based cardio issue with B12.
Also I posted an ear question to this group.that I’m having. Since I ramped up fitness my ear has been getting worse ?!
hi BeachArt - I have the same issue. I am fine walking 5-6 km a day. I recently tried to train for a 5km run with walk/ run intervals. Felt fine while doing it but then crashed for several days after. It is a form of PEM - Post Exercise Malaise. You can read some studies on it. It might be that we have to be very slow in opening up the length of our exercise windows to stay within what the studies refer to as your “envelope ”.
Is it a coincidence that all the symptoms of PEM is the same as B12D?
Maybe start with some exercises that do not involve pounding on your legs? Skipping and jogging are VERY high impact. I love dancing. Is there a Zumba or other dance exercise class you could take? Swimming or water fit. Biking- an e-bike would allow you to make a gentle start with this. Ice or roller skating. A rowing machine. There are lots of alternatives that are not as high impact on your legs and feet.
Rowing machine, and exercise bike, also cause this issue. It just seems to be higher intensity cardio that is the problem. I did have to laugh at your suggestions, not because they are funny or anything, but because I cannot swim, and have never had the balance to roller skate or ice skate. I would end up with more problems if I did those lol. But thank you for your suggestions.
Can you explain though why you think high impact exercises could cause this issue please? Thanks
i've got the same issue and like you, always wondered about the correlation and endurance exercises. I get the PEM when I do any kind of jogging. My endurance was never great to begin with and I dont think its a cardiovascular issue. Even when I was jogging regularly for 3 miles 2-3 times a week prediagnosis, I coudnt run fast. I'd have to go at a slow pace because I would start getting lactic acid build up if I tried to push it. There must be something going on at the cellular level that makes it difficult for our bodies to use the B12 efficiently even if its readily available.
Your example would definitely support my theory about a lower anaerobic threshold as lactic acid is a by product of anaerobic energy metabolism. It sounds as if you had to jog at a slower pace to keep your heart rate at a lower rate so that you avoid crossing this threshold. Normally we can train to raise this threshold but not sure if the same is true for those of us with autoimmune issues.
B12 and exercise
B12 deficiency 
B12 deficiency 
