Achilles tendon ruptures are debilitating injuries that lead to long-term functional deficits in two thirds of patients. Shear wave tensiometry is a non-invasive technique for measuring tendon loading during functional activities by inducing waves traveling along the tendon and measuring their propagation speed. Tensiometers have the potential to be implemented in clinical settings to objectively track tendon loading to assist in clinical decision-making. Purpose: To determine whether shear wave tensiometry can detect abnormalities in tendon loading during recovery following Achilles tendon rupture and repair. Methods: Tensiometers were placed bilaterally on the Achilles tendons of one subject who had undergone surgical repair of a unilateral Achilles tendon rupture 14 weeks prior (M, 87.6 kg, 193 cm) and two control subjects (M, 75.0 kg, 188 cm; M, 100.0 kg, 185 cm). Each subject first performed isometric ankle plantarflexion contractions while wave speed and joint torque were measured. Tendon force was estimated from torque by assuming a normative 5 cm Achilles moment arm. Isometric data were used to calibrate a linear model for predicting tendon force from wave speed squared. The subject then walked on a treadmill (patient: 1.25 m/s; controls: 1.50 m/s) while Achilles tendon wave speed was recorded bilaterally. Plantarflexor impulse was calculated by integrating predicted tendon force over each stance phase. Results: We estimate that the patient produced a 40% lower plantarflexor impulse on the injured side (4.8 ± 0.4 N·s·kg^-1; mean ± SD) compared to the healthy side (8.0 ± 1.0 N·s·kg^-1), while the side-to-side differences for control subjects were 5% (8.4 ± 0.4 N·s·kg^-1 vs. 8.0 ± 0.2 N·s·kg^-1) and 2% (10.7 ± 0.7 N·s·kg^-1 vs. 10.5 ± 1.0 N·s·kg^-1), respectively. Conclusion: Tensiometer data show that the patient adopted a gait pattern that underloaded the healing tendon. This is important to consider given that early loading exposure may be an important determinant of long-term healing and structure of the repaired tissue. This study establishes the feasibility of using shear wave tensiometry to quantify tendon load during clinical assessments of patients with tendon injuries, which is an unmet clinical need. Supported by the Thomas B. and Jeannette E. Laws McCabe Fund and the Wisconsin Alumni Research Foundation.