Congenital muscular dystrophies (CMDs) are congenital onset muscular dystrophies, with laminin alpha-2 (LAMA2) and collagen VI (COL6)-related dystrophies (RD) being the most common subtypes. Symptoms include hypotonia, progressive muscle weakness, respiratory insufficiency and joint contractures. The assessment of muscle weakness and motor capacity in children is essential for future therapeutic clinical trials. Myometry uses a hand-held device to quantitatively measure muscle strength. Based on the individual’s weight, sex, age, and exerted force, normative percentages are calculated. The Graded Functional Test (GFT) is an assessment that measures supine to stand (STS), run 10 meters, and ascend/descend four steps. These skills are timed and scored qualitatively, with a higher score indicating better performance. This exploratory analysis aims to compare the myometry normative percentages and the graded functional test qualitative scores from the baseline visit of participants with LAMA2-RD and COL6-RD, 6 years and older. The myometry assessment and GFT were administered to 32 participants: 3 with LAMA-2 (9.38%) and 29 COL6-RD (90.62%). Of the 32 participants, 16 were male with a mean age of 9.68 ± 3.02 years. Using Spearman’s rank correlation, there was a statistically significant strong correlation between the STS and 10-meter run (ρ = 0.67, p < 0.001). We found statistically significant moderate correlations between STS and knee extensors (ρ = 0.40, p = 0.03), elbow flexors (ρ = 0.45, p = 0.014), and elbow extensors (ρ = 0.52, p = 0.004) and between 10-meter run and hip abductors (ρ = 0.53, p = 0.005) and elbow flexors (ρ = 0.45, p = 0.01). Statistically non-significant weak correlations were present between both functional tests and knee flexors (ρ = 0.17 – 0.32, p = 0.08 – 0.37). Additional studies are needed to propose the use of myometry as a predictor of an individual’s motor capacity.