Initial internal construct validation of the Mito Map Energy Score against a separately recorded composite of grip strength, five-times sit-to-stand performance, baseline fatigue, and post-task fatigue. The primary pipeline-defined analysis included 21 participants. The Energy Score was strongly associated with the Measured Function Score (Pearson r = 0.907; 95% CI 0.781 to 0.962), with supporting rank-correlation, leave-one-out, objective-only, protocol, and agreement analyses. These findings support initial convergent construct validity but do not establish diagnostic validity, clinical utility, or prospective prediction. The accompanying publication package contains aggregate results and de-identified figures only; it contains no direct identifiers or row-level participant records.