- Elevated circulating creatine kinase activity (HP:0003236): The activity of creatine kinase in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 172/174. (PMID:22250184;PMID:21880526)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 1/6. (PMID:21880526)
- Middle age onset (HP:0003596): A type of adult onset with onset of symptoms at the age of 40 to 60 years. Evidence: PCS. Frequency: 1/6. (PMID:21880526)
- Rhabdomyolysis (HP:0003201): Breakdown of muscle fibers that leads to the release of muscle fiber contents (myoglobin) into the bloodstream. Evidence: PCS. Frequency: 3/6. (PMID:21880526)
- Failure to elevate ammonia on ischemic exercise (HP:6000320): Normal subjects display an increase in the concentration of ammonia in the blood following an ischemic exercise test. This term refers to an increase in ammonia that is below the lower limit of normal. Evidence: PCS. Frequency: 3/3. (PMID:3476851)
- Reduced muscle glycogen phosphorylase activity (HP:6000358): Activity of the enzyme glycogen phosphorylase in muscle tissue is below the lower limit of normal. Glycogen phosphorylase (EC 2.4.1.1) is also known as amylophosphorylase, muscle phosphorylase a and b, polyphosphorylase, and myophosphorylase. Evidence: PCS. Frequency: 4/4. (PMID:21880526)
- Failure to elevate lactate upon ischemic exercise test (HP:6000526): Failure to elevate lactate in blood washed out from ischemically exercised muscles as assayed by the forearm ischemic exercise test. Evidence: PCS. (PMID:3476851)
- Exercise-induced rhabdomyolysis (HP:0009045): Rhabdomyolysis induced by exercise. Evidence: PCS. (PMID:8316268)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 4/6. (PMID:21880526)
- Myoglobinuria (HP:0002913): Presence of myoglobin in the urine. Evidence: PCS. Frequency: 101/202. (PMID:22250184;PMID:21880526)
- Exercise-induced myalgia (HP:0003738): The occurrence of an unusually high amount of muscle pain following exercise. Evidence: PCS. (PMID:8316268)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:8316268)
- Dark urine (HP:0040319): An abnormal dark color of the urine. Evidence: IEA. (OMIM:232600)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: PCS. Frequency: 49/196. (PMID:22250184)
- Exercise-induced muscle cramps (HP:0003710): Sudden and involuntary contractions of one or more muscles brought on by physical exertion. Evidence: PCS. (PMID:8316268)
- Hyperuricemia (HP:0002149): The concentration of uric acid in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 2/5. (PMID:21880526)
- Exercise intolerance (HP:0003546): A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender. Evidence: PCS. (PMID:21880526)
These phenotypes are associated with the disease glycogen storage disease V (OMIM:232600).