Hi, despite daily injections giving me my quality of life back so I can work and generally function, I am finding getting back to running much more difficult. It’s been over 3 months of injections now, and I still don’t feel like I can run properly. It seems very hard and my fitness doesn’t improve even with consistent light training. I want to get back to running ultramarathons but it seems so impossible to imagine most days. Does anyone have experience of running or exercise after P.A. treatment? How much extra B12 does exercise use up? I guess it’s so individual but I can’t even find any information or research about it, and just feel like I’m feeling my way in the dark at the moment.
Thanks so much to this forum giving me so much help over the last few months.
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Jengastar
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I don't think exercise uses up any extra B12, there's no reason why it should.
What I've found is that I can do gentle exercise for very long periods but with moderate exercise I hit a limit within a minute or two.
While I was never into running marathons (or even running for a marathon chocolate bar) I was keen on watching and photographing birds. That would often mean walking miles carrying around 15 kg of camera, lenses, bins, scope and tripod. As my illness progressed the amount I could carry, and the distance I could walk got smaller and smaller. Until walking 50m from the car park to the doctors was too much.
After treatment I regained some of my stamina. I can now walk miles, if I'm carrying nothing. But even my good binoculars are too heavy at 845 g and I've had to buy a cheaper, lighter pair. If I try carrying 5 kg for a minute then I need 5 minutes rest, gasping for air.
And that's been the same whether I inject every other day or every other week. Short bursts of moderate exercise wipe me out.
Now that may just be me. You might be different.
I was about to recommend that you ask your doctor to increase the frequency of your injections, but I see you're already injecting daily.
Have you and to doc looked at other possible causes for your fatigue?
Hi, thanks for taking the time to reply it's really helpful. I assumed B12 would be affected by exercise due to it using red blood cells, metabolism and muscle repair and had thought B12 use would increase as the requirements for these functions increased. Do you think I am being too simplistic in that assumption? I guess it might be worth me trying some long walks and comparing it to a shorter run and seeing how it feels. I think I feel like I could walk pretty far at moment, and like you it was just the higher intensity or sharp hills.
While B12 is involved in making red blood cells, and muscle cells, those activities aren't going to be increased significantly, no matter how much exercise you take.
It also plays a small part in the cell's mechanism for generating energy. But it is only the metabolism of fatty acids with an odd number of carbon atoms, cholesterol, and a few amino acids, that require B12. en.wikipedia.org/wiki/Propi...
The vast majority of the body's energy is produced by the oxidation of glucose - which doesn't involve B12.
So I've no idea why it takes a long time to build up stamina for some people. And I'm not sure anybody does. Nor why it's so variable - with some people taking years to get anywhere close to there they were previously, while others are back to normal in just months.
I always suggest doing what I did - start slow and build it up without pushing yourself too hard.
I would really take your time as it sounds as though you are doing tedlly well on daily injections.
Exercise I think will have tk be moderated .
I've found even a slight incline walking really affects me .
I cant seem to be able to carry anything
I've never been a runner.
I was used to cycling . More as transport than a hobby. I never took the car to town as coukd cycle by a river . I miss that. I miss the freedom of a bike.
I also hope to get back to it at some stage. At the moment I get too weak or off balance to walk far . Often it just hits mh head. Some days I'm much stronger t8 walk. What I find difficult is there seems no pattern or rhyme or reason.
I think we are all feeling out way in the dark. The research is just nit there. Aks8 everyone seems to react in different ways.
So enjoy how far you have come and hopefully you can build ti a run.
My husband misses running. Had to stop because of arthritic knees! Even with the best of trainers!!
Have you though of having your thyroid tested ? Exhaustion can be a symptom apparently ... I often read on this forum that many P.A. patients have thyroid problems as well . Auto-immune conditions seldom come alone and both conditions are autoimmune . I read that the NHS thyroid test is not thorough enough . A private one gives more information .
Thanks - I haven't looked into thyroid at all, but will do. I guess after years of deblitating fatigue I feel so much better on B12, but maybe just missing that last bit of energy for running.
No offense intended, but fbirder's response is scientifically inaccurate.
Although dated, this article still adequately explains the pervasive role that the B Vitamins (i.e., necessary micronutrients for your body) play in exercise:
"Regular physical activity may alter the need or requirements for some micronutrients in several ways. First, the metabolic pathways that produce energy are stressed during physical activity; thus, requirements for some of the nutrients used in these pathways may increase. Second, biochemical adaptations that occur with training in the tissues of the body may increase requirements. Third, strenuous exercise may also increase the turnover or loss of a particular micronutrient in sweat, urine, or feces. Finally, additional micronutrients may be required to repair and maintain the higher lean tissue mass of some athletes and active individuals."
Thanks this is really helpful and exactly what I had been trying to find. I think I’ll also try to contact the researchers and discuss or find experts more local to me. Thanks so much for finding these for me I really appreciate it!
I’d say it took me a couple of years to return to fitness in cycling. During that time I took my injection frequency from once every 2 months on diagnosis (no loading injections received) to twice a week where I’ve settled for the last couple of years.
At the start I could barely cycle a few miles (having previously cycled long distances) and would be exhausted. Then as my fitness slowly improved I could get my distance up but not my speed.
And finally I’m pleased to say that in the last couple of years I’ve been able to up my pace and maintain my distance.
I definitely need to have recovery days and I’m certainly exhausted by the evening. Having said that on a non cycling day I’m ready to put my feet up by mid afternoon!
My fitness is affected by alcohol so I keep that to a maximum of couple of glasses once a week. Slipped up this week as celebrating an anniversary on Monday I had a large glass of wine and a glass and a half of champagne and I was definitely under par on my bike today. Nevertheless I was with a fast group and we did 100km.
So it might be that you just need time to recover from your previous deficiency and then time to rebuild your fitness (slowly and factoring in recovery days) now that you’re on adequate treatment?
Belated thanks for your reply - I will just keep doing what I can, and see if I can gardually increase my volume and intensity. Did you use any heart rate data in your training? I think will use my monitor to see if I can see any improvements, but also relax a bit and just appreciate what I can do.
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