Evidence for strengthening

Question 1

What studies do you want to cite for strengthening?

Answer 1

Role of acl:
- Evans Mabrouk & Neilson, 2023 review

Strengthening glute med:
- Maniar et al, 2022 sys review
- Paterno et al, 2010 cohort study

Strengthening hamstrings:
- Maniar et al, 2022 sys review (overall)
- Stojanovic et al, clinical trial (eccentrics)
- Nunes et al, umbrella review (NHE)

Strengthening soleus:
- Maniar et al, 2022 sys review

Question 2

What is the role of the ACL?

Answer 2

Evans, Mabrouk and Nielson, 2023

The role of the ACL is to stabilise the knee joint

Question 3

What do the two fibre bundles of the ACL do?

Answer 3

Evans, Mabrouk and Nielson, 2023

• the anteromedial bundle is mainly responsible for minimising anterior tibial translation
• the posterolateral bundle’s main role is providing medial-lateral and rotational stability

Question 4

What evidence do you have for including glute med strengthening?

Answer 4

Maniar et al 2022 – systematic review

• knee valgus collapse reported to be common mechanism of injury in video-based analyses
• gluteus medius opposes knee valgus more than any other muscle during weightbearing tasks, thus unloading the ACL
• hence including the clam shell side planks to target glute med
• BUT the majority of the evidence comes from cadaveric and musculoskeletal modelling studies, with less evidence from in vivo methods

Question 5

What other evidence do you have for including glute med?

Answer 5

Paterno et al (2010) – cohort study
- level of evidence – 3
- 56 athletes underwent biomechanical screening post ACLR and then were followed for a year to see if they reinjured
- of the 13 who reinjured, an increase in valgus movement and deficit in single leg postural stability predicted a second injury with excellent sensitivity and specificity
- hence including the clam shell side planks to target glute med

Question 6

What evidence do you have for strengthening hamstrings?

Answer 6

Maniar et al 2022 – systematic review

• The hamstrings…. are effective at unloading the ACL by generating posterior shear forces at the tibia
• BUT the majority of the evidence comes from cadaveric and musculoskeletal modelling studies, with less evidence from in vivo methods
• Hence including hamstring exercises – prone back extensions with leg weights, bridge, deadlift, Nordic etc

Question 7

What evidence do you have for the nordic hamstring exercise?

Answer 7

Nunes et al 2024 – umbrella review of effects of Nordic hamstring exercise

• 10 systematic reviews included, encompassing 125 studies, enrolling 17,260 subjects
• one of the most consistent findings across the studies was that the NHE has the potential to increase the knee flexors’ eccentric strength

Question 8

What evidence do you have for including eccentric strength exercise for hamstrings?

Answer 8

Stojanovic et al (2023) – clinical trial
- eccentric-oriented strength training in late-stage ACL recovery results in better outcomes than traditional strength training in professional team sport athletes
- BUT
o small study n=22
o study looked at eccentric training undertaken twice or three times weekly for 6 weeks, which is more than we have in this programme
- hence we have included targeted eccentrics in double leg bridge on Swiss ball, Nordic hamstring exercise, single leg deadlift

Question 9

What evidence do you have for including jumping/ hopping exercises?

Answer 9

Maniar et al 2022 – systematic review
- …Soleus [is] effective at unloading the ACL by generating posterior shear forces at the tibia
- BUT the majority of the evidence comes from cadaveric and musculoskeletal modelling studies, with less evidence from in vivo methods
- (Soleus originates on posterior surface of tibia)
- Hence we have included lots of jumping exercises ie forceful plantar flexion of ankle to load soleus