Sounds like a plan to me! I will keep reaching out to other medical fields to see if anyone else has any ideas.
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Thanks!
Clarky07920 said:That sounds like a form of metabolic myopathy to me Shayne so I'd not be surprised if this was the culprit. I'm back I the NHS now so not sure when I'll next see consultant neurologist but I'll mention it. My MRI came back clear yesterday.
I suspect it is this is what I (and possibly some others) may have. I saw the rheumatologist yesterday and whilst not her field of expertise she thinks this is much more likely than myositis - which is a good thing!
The down side is that the key "management" of the condition would appear to be cutting out prolonged/strenuous exercise.
jsk said:The symptoms definitely sound right, but the cause/triggers don't seem to fit. Reading that first link, it sounds like the problem arises when the body is forced to use fat for fuel (due to duration of exercise, fasted state, or high-fat diet). That seems like exactly the opposite of what seems to happen with me; my problem comes from too much carbs and rest, not too much fat and exercise. I have no problem training in a fasted state, and seem to be pretty good at burning fat during exercise (eg riding for 3 hours with minimal calorie intake). I certainly don't think that going on a high-carb, low-fat diet would be the best way to manage this condition for me.
I still think the underlying mechanism may be more like tying up in horses (http://www.thehorse.com/articles/27500/tying-up-in-horses-a-review)
Shayne_G said:[quote=" Although, I have had cramping during a block of training as well, so that symptom sometimes doesn't hold true for me.
budegan said:Shayne_G said:[quote=" Although, I have had cramping during a block of training as well, so that symptom sometimes doesn't hold true for me.
I find this line interesting (and very scary) as I thought that one of the common factors between us was that the condition was only triggered by a period of inactivity.
Shayne_G said:budegan said:Shayne_G said:[quote=" Although, I have had cramping during a block of training as well, so that symptom sometimes doesn't hold true for me.
I find this line interesting (and very scary) as I thought that one of the common factors between us was that the condition was only triggered by a period of inactivity.
This recently started happening to me. Whatever this condition is, it does seem to be progressing for me personally as the episodes have become more frequent, lasted longer, and have been more intense. A couple of years ago I could usually work through them via frequent exercise, but recently the cramps have come about during a solid block of riding 6 days a week. This is the reason I started doing further research and am less convinced it is McArdles (tying up) at this point.
This excerpt is from an interesting article I read yesterday evening:
"Metabolic myopathies — Rhabdomyolysis may develop in patients with abnormal muscle, such as individuals with inherited disorders of glycogenolysis, glycolysis, or lipid metabolism (table 2). These disorders are discussed in detail separately. (See "Metabolic myopathies caused by disorders of lipid and purine metabolism" and "Overview of inherited disorders of glucose and glycogen metabolism".)
The metabolic myopathies represent a very small percentage of cases of rhabdomyolysis overall but are relatively common causes among patients with recurrent episodes of rhabdomyolysis after exertion [34,35]. In a series of 77 patients evaluated for "idiopathic" myoglobinuria in whom muscle biopsies were performed, specific enzyme deficiencies were identified in 36 (47 percent) [35]. Carnitine palmitoyltransferase deficiency was the most common disorder, occurring in 17 of the 36 patients, followed by muscle phosphorylase deficiency (McArdle disease) in 10. (See "Metabolic myopathies caused by disorders of lipid and purine metabolism", section on 'Fatty acid transport defects' and "Myophosphorylase deficiency (glycogen storage disease V, McArdle disease)".)
The precise mechanism of muscle necrosis in the metabolic myopathies has not yet been established, but it is likely that insufficient energy production in exercising muscle leads to depletion of adenosine triphosphate (ATP) and creatine phosphate. The maintenance of muscle cell integrity is thereby compromised [36]. (See "Approach to the metabolic myopathies", section on 'Myoglobinuria and rhabdomyolysis' and "Energy metabolism in muscle" and 'Pathophysiology' above.)
Postexertional rhabdomyolysis has also been described in individuals with mitochondrial myopathies due to defects in respiratory chain enzymes [37]."
Full text here: http://www.uptodate.com/contents/causes-of-rhabdomyolysis
budegan said:I'm really surprised it's that long as I'd have thought it's just a case of the wound healing.
Wow! I hope they can make a precise determination...Shayne_G said:budegan said:I'm really surprised it's that long as I'd have thought it's just a case of the wound healing.
The wound isn't the issue, it's the amount of quad muscle they have to take (~a cubic centimeter). Taking that much tissue increases the risk of quad rupture which is why the protocol is so conservative.