Unit 15 Assignment 3. Applying treatment methods and designing rehabilitation methods.
Injury: 100 metre sprinter with a grade 2 hamstring muscle tear.
(Dutch, 2017) (Spink, 2015)
Risk factors associated with a hamstring tear
• The sport: Liu et al., (2012) found that 94% of hamstring tears occur from running activities.
Sprinting full speed running so this injury risk factor is hard to eliminate as it is easy to stride
too hard or too far.
(Bialowas, 2019)
• Shortened optimum muscle length: Legs with hamstring muscle strain injury histories may
have shorter optimum hamstring muscle lengths and thus higher muscle strains in
comparison to legs without injury histories for the same range of motion (Brockett, Morgan
and Proske, 2004). It is possible to reduce this risk factor through active release therapy to
soften scar tissue.
, (Hile, 2022)
• Lack of muscle flexibility: Athletes with poor hamstring flexibility may have shorter optimum
hamstring muscle lengths in comparison to athletes with normal hamstring flexibility. As
previously discussed, shorter optimum muscle length may result in higher muscle strain for
the same range of motion, and thus increase the risk for hamstring strain injury. This risk can
be reduced through specific hamstring flexibility training using static, dynamic, and
proprioceptive neuromuscular facilitation (PNF) stretching.
(Leaman, 2021)
• Strength imbalance: Croisier et al., (2008) found that athletes with uncorrected preseason
hamstring strength imbalance had a significantly higher rate of hamstring strain injury in
comparison to those without preseason hamstring strength imbalance, and to those with
, corrected preseason hamstring strength imbalance. This is because certain muscles will work
harder to overcompensate for the weaker muscles, leading to pain and injury. This risk
factor can be improved by using unilateral exercises or isolated exercises to target the
weaker muscles.
(Hile, 2022)
• Insufficient warm-up: Insufficient warm-up is a risk factor for hamstring muscle strain injury
as many hamstring muscle strain injuries occur during the early portions of practices or
competitions (Ekstrand and Gillquist, 1982). This is because the muscle temperature and
elasticity are reduced so the muscle length is reduced, leading to a higher risk of tearing
muscle fibres. This injury risk can be avoided by doing a thorough warm up including gentle
range of movement exercises, warm-up exercises, stretching, mobility exercises, technical
drills, and speed running.
(MyDr, 2019)
• Fatigue: Fatigue is also a risk factor for hamstring muscle strain injury as they can often
occur during the late portions of practices and competitions (Brooks et al., 2006; Ekstrand
and Gillquist, 1982; Woods et al., 2004). This is because fatigued muscles absorb more
energy, leading to increased muscle elongation, sub–optimal muscle length and risk of
strains (Mair et al., 1996; Small et al., 2010). This risk can be reduced by avoiding
overtraining and optimal recovery using methods like cryotherapy, deep tissue massage, and
nutrional supplementation.
, (Keay, 2018)
• Low back injury: Lower back injuries or lumbar disorder has been associated with hamstring
strain injury (Devlin, 2000). This is because people with back pain often have decreased
hamstring flexibility (Mooney and Robertson, 1976) suggesting that low back pain provokes
hamstring responses such as increased tension and results in muscle damage (Devlin, 2000).
Hennessey and Watson (1993) found a significant increase of lumbar lordosis among
hamstring injured athletes, indicating an association between hamstring strain injury and
lumbar posture. This suggests that there is a strong interdependence between back
pain/posture and hamstring injuries. This means that this risk factor can be reduced by fixing
posture with strengthening and stretching the muscles in the back and core whilst
maintaining strong and flexible hamstrings.
• Increased muscle neural tension: Abnormal neural tension is a risk factor for the recurrence
of hamstring strain injuries (Turl and George, 1998). Branches of the sciatic nerve can be
tethered to the scar after a hamstring injury and create increased neural tension with or
without local irritation, which may result in local damage to the hamstring muscle (Delvin,
2000). This risk factor can be decreased by using active release therapy and instrument
assisted soft tissue mobilisation as these techniques decrease muscle adhesions which un–
restricts nerves, leading to decreased neural tension.
(Santana et al., 2015)
• Muscle compositions: Garrett Jr, Califf and Bassett (1984) noticed that muscles comprised of
a high percentage of fast fibres and low oxidative capacity were prone to strain injury on a
higher severity with less strain compared to muscles not prone to strain injury, and
hamstring muscles have a relatively high percentage of Type II fibres compared to other
lower extremity muscles, especially if the fast twitch muscle fibres produce and absorb lots
of eccentric force (Friden, and Lieber, 1992; Macpherson et al., 1996). There is evidence that
muscle composition can be slightly altered through long–term training (Plotkin et al., 2021),
but as 100m sprint requires lots of type II muscle fibres, this risk factor cannot be reduced so
attention should go towards modifying other risk factors.
Injury: 100 metre sprinter with a grade 2 hamstring muscle tear.
(Dutch, 2017) (Spink, 2015)
Risk factors associated with a hamstring tear
• The sport: Liu et al., (2012) found that 94% of hamstring tears occur from running activities.
Sprinting full speed running so this injury risk factor is hard to eliminate as it is easy to stride
too hard or too far.
(Bialowas, 2019)
• Shortened optimum muscle length: Legs with hamstring muscle strain injury histories may
have shorter optimum hamstring muscle lengths and thus higher muscle strains in
comparison to legs without injury histories for the same range of motion (Brockett, Morgan
and Proske, 2004). It is possible to reduce this risk factor through active release therapy to
soften scar tissue.
, (Hile, 2022)
• Lack of muscle flexibility: Athletes with poor hamstring flexibility may have shorter optimum
hamstring muscle lengths in comparison to athletes with normal hamstring flexibility. As
previously discussed, shorter optimum muscle length may result in higher muscle strain for
the same range of motion, and thus increase the risk for hamstring strain injury. This risk can
be reduced through specific hamstring flexibility training using static, dynamic, and
proprioceptive neuromuscular facilitation (PNF) stretching.
(Leaman, 2021)
• Strength imbalance: Croisier et al., (2008) found that athletes with uncorrected preseason
hamstring strength imbalance had a significantly higher rate of hamstring strain injury in
comparison to those without preseason hamstring strength imbalance, and to those with
, corrected preseason hamstring strength imbalance. This is because certain muscles will work
harder to overcompensate for the weaker muscles, leading to pain and injury. This risk
factor can be improved by using unilateral exercises or isolated exercises to target the
weaker muscles.
(Hile, 2022)
• Insufficient warm-up: Insufficient warm-up is a risk factor for hamstring muscle strain injury
as many hamstring muscle strain injuries occur during the early portions of practices or
competitions (Ekstrand and Gillquist, 1982). This is because the muscle temperature and
elasticity are reduced so the muscle length is reduced, leading to a higher risk of tearing
muscle fibres. This injury risk can be avoided by doing a thorough warm up including gentle
range of movement exercises, warm-up exercises, stretching, mobility exercises, technical
drills, and speed running.
(MyDr, 2019)
• Fatigue: Fatigue is also a risk factor for hamstring muscle strain injury as they can often
occur during the late portions of practices and competitions (Brooks et al., 2006; Ekstrand
and Gillquist, 1982; Woods et al., 2004). This is because fatigued muscles absorb more
energy, leading to increased muscle elongation, sub–optimal muscle length and risk of
strains (Mair et al., 1996; Small et al., 2010). This risk can be reduced by avoiding
overtraining and optimal recovery using methods like cryotherapy, deep tissue massage, and
nutrional supplementation.
, (Keay, 2018)
• Low back injury: Lower back injuries or lumbar disorder has been associated with hamstring
strain injury (Devlin, 2000). This is because people with back pain often have decreased
hamstring flexibility (Mooney and Robertson, 1976) suggesting that low back pain provokes
hamstring responses such as increased tension and results in muscle damage (Devlin, 2000).
Hennessey and Watson (1993) found a significant increase of lumbar lordosis among
hamstring injured athletes, indicating an association between hamstring strain injury and
lumbar posture. This suggests that there is a strong interdependence between back
pain/posture and hamstring injuries. This means that this risk factor can be reduced by fixing
posture with strengthening and stretching the muscles in the back and core whilst
maintaining strong and flexible hamstrings.
• Increased muscle neural tension: Abnormal neural tension is a risk factor for the recurrence
of hamstring strain injuries (Turl and George, 1998). Branches of the sciatic nerve can be
tethered to the scar after a hamstring injury and create increased neural tension with or
without local irritation, which may result in local damage to the hamstring muscle (Delvin,
2000). This risk factor can be decreased by using active release therapy and instrument
assisted soft tissue mobilisation as these techniques decrease muscle adhesions which un–
restricts nerves, leading to decreased neural tension.
(Santana et al., 2015)
• Muscle compositions: Garrett Jr, Califf and Bassett (1984) noticed that muscles comprised of
a high percentage of fast fibres and low oxidative capacity were prone to strain injury on a
higher severity with less strain compared to muscles not prone to strain injury, and
hamstring muscles have a relatively high percentage of Type II fibres compared to other
lower extremity muscles, especially if the fast twitch muscle fibres produce and absorb lots
of eccentric force (Friden, and Lieber, 1992; Macpherson et al., 1996). There is evidence that
muscle composition can be slightly altered through long–term training (Plotkin et al., 2021),
but as 100m sprint requires lots of type II muscle fibres, this risk factor cannot be reduced so
attention should go towards modifying other risk factors.
