55419
document
The effects of orthotic heel lifts on Achilles tendon force and strain during running . This study assessed the effects of orthotic heel lifts on Achilles tendon ( AT ) force and strain during running . Ten females ran barefoot over a force plate in three conditions : no heel lifts ( NHL ) , with 12 mm heel lifts ( 12HL ) and with 18 mm heel lifts ( 18HL ) . Kinematics for the right lower limb were collected ( 200 Hz ) . AT force was calculated from inverse dynamics . AT strain was determined from kinematics and ultrasound images of medial gastrocnemius ( 50 Hz ) . Peak AT strain was less for 18HL ( 5.5 ± 4.4 % ) than for NHL ( 7.4 ± 4.2 % ) ( p = .029 , effect size [ ES ] = 0.44 ) but not for 12HL ( 5.8 ± 4.8 % ) versus NHL ( ES = 0.35 ) . Peak AT force was significantly ( p = .024 , ES = 0.42 ) less for 18HL ( 2382 ± 717 N ) than for NHL ( 2710 ± 830 N ) but not for 12HL ( 2538 ± 823 N , ES = 0.21 ) . The 18HL reduced ankle dorsiflexion but not flexion-extension ankle moments and increased the AT moment arm compared with NHL . Thus , 18HL reduced force and strain on the AT during running via a reduction in dorsiflexion , which lengthened the AT moment arm . Therefore , heel lifts could be used to reduce AT loading and strain during the rehabilitation of AT injuries .
55420
Intervention_Physical
orthotic heel lifts
55421
Intervention_Physical
orthotic heel lifts
55422
Intervention_Control
no heel lifts
55423
Intervention_Physical
12 mm heel lifts
55424
Intervention_Physical
18 mm heel lifts
55425
Outcome_Physical
Achilles tendon force and strain
55426
Outcome_Physical
Achilles tendon ( AT ) force and strain
55427
Outcome_Physical
Kinematics for the right lower limb
55428
Outcome_Physical
AT strain
55429
Outcome_Physical
Peak AT strain
55430
Participant_Sample-size
Ten
55431
Participant_Sex
females