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Prevention and Rehabilitation: Rowing
Chris Mallac looks at the most typical injuries in this popular Olympic sport.
Rowing is a strenuous sport that has huge worldwide appeal. Olympic gold medal winners will have instant household fame. Rowers race against each other in boats, either on lakes, specifically designed rowing regatta courses, rivers, and open ocean (surf boat rowing). Boats are propelled by the reaction forces on the oar blades as they are pushed in and against the water.
Participation in the sport suits all body types and heights. Elite level rowers tend to be taller and leaner individuals as the longer limb mechanics are advantageous in developing the necessary stroke length and force to gain maximum boat velocity. However, it is this height and leverage that often leads to the common injuries seen
Typical events are rowed over 2000m at Olympic level and this takes in the vicinity of 5-6 minutes to complete. The primary physiological attributes needed are:
1. Aerobic fitness. Elite rowers tend to have enormous lung capacity and cardiac stroke volume also characterised by high VO2 max levels.
2. Anaerobic tolerance. The repetitive hip flexion/knee flexion to hip extension/knee extension positions uses drive in the large power muscles in the quadriceps, hamstrings, gluteals and back extensors. The lactic acid spikes in elite level competition can be quite dramatic requiring that the rower have a high lactic tolerance and efficient buffer systems.
3. Strength. Lower limb push-and-pull strength and back extensors strength are paramount. Upper body strength required is the pull strength generated by the scapular retractors, shoulder extensors and elbow flexors.
4. Coordination. Rowing in a team of four or eight requires a high level of precision between all team members. The nature of the action/reaction of the rower moving in the boat ensures that if rowers are ‘out of sync’ then this will be visualised as a slowing of the boat in the water.
Types of rowing
There are two primary type of rowing.
a) Sweep oar. One oar per athlete with the oar to the left known as the bow side, and the oar to the right known as the stroke side. The stroke side rowers tend to be the more technically proficient rowers and set the rhythm for the other rowers.
b) Sculling. Two oars per athlete.
Training volumes vary amongst rowing countries and amongst age groups. Training may consist of steady state aerobic on-water training and land-based ergometer training (total distances may be as high as 300km per week for an Olympic level team), interval training of high-intensity efforts over 250-1000m, resistance training (tyre, rope or crate dragging). Furthermore, rowers may also spend time in up to four gym- based sessions per week focusing on lower limb pull-and-push strength and upper body pull strength. Core stability training also forms a large part of the preparation of the rower as well as cross-training with the favoured crossover sport being cycling.
Biomechanics of rowing
1. The catch. The catch starts in full hip flexion, knee flexion, varying degrees of trunk flexion, shoulder flexion and elbow extension. The purpose is to reach as far forward as possible to maximise the start position prior to the pull. This catch position determines the overall stroke length.
2. The pull. When the blade engages the water, there is a powerful contraction of the quadriceps, gluteals and back extensors. Peak muscle activity begins just after the pull begins and this is also where the spinal loads are the greatest. The body is being pushed back into knee and hip extension whilst the arms pull into shoulder extension and elbow flexion. The boat will accelerate and pick up speed as the rowers body movement is transferred as force into the oar and blade in the water. The pull finishes as the knees fully extend and the elbows fully flex to pull the handle into the rower’s stomach area.
3. The recovery. The rower will momen-tarily pause at the end of the pull phase and then initiate the recovery by dropping the handle to pick the blade up out from the water. The blade is then free to move above the water. The rower then rapidly flexes the hips and knees and pushes the handle away from the body using elbow extension and shoulder flexion. The rower is searching for the new catch position.
Rowers typically spend time on water in daily rowing sessions, ranging from intense interval-type sets to low-intensity volume rowing sets. However, they also spend significant time participating in dry-land strength and conditioning training. Running, cycling and rowing ergometers are commonly used methods and 2-3 gym sessions per week are also common.
The typical content of the gym sessions may vary from country to country and between age groups; however, the common lifts used for the rower include :
2. Leg press
3. Deadlift (and variations)
4. Olympic lifts (cleans, high pulls, split cleans, snatch etc)
5. Prone pulls
7. Seated row
These exercises all add a significant compressive load to the spine and the cumulative effect of the lifting on top of the on-water rowing and off-water conditioning needs to be considered when discussing the nature of the injuries that rowers suffer from.
Common sites of injuries in rowers
Evidence taken from junior rowers demonstrates that 74% of injuries are overuse in nature and 26% were related to a single event. Female injury rates are much higher than male rates (about 20% more common). The lower back is the most injured site (41%), followed by the knee and then wrist. The main risk factors identified are changing sides, fewer years of experience and greater than seven training sessions per week (Smoljanovi et al 2009).
The main injury sites are:
1. The wrist and hand
2. The forearm
1. Wrist and hand
Intersection syndrome is an irritation in the wrist tendons where the abductor pollucis longus (APL) and extensor pollucis longus (EPL) tendons cross in the wrist. The rower will feel pain, a grating or crepitus sensation over the tendon region (5-8cm proximal to the wrist) during wrist flexion/extension, and may be associated with some swelling in the tendons.
The primary causative factor in the development of intersection syndrome relates to repetitive feathering of the wrist in the recovery phase of rowing. Furthermore, handles which are too large in diameter and using ‘too tight’ a grip are other factors related to the development of wrist problems. Finally, the changeover from sweep rowing to sculling which requires more feathering of the wrist may also lead to an intersection syndrome.
Investigations for intersection syndrome consist of ultrasound which may show the fluid in the sheaths surrounding the APL/EPL tendons. As then tendons are superficial, the swelling is easily visualised under an ultrasound.
The focus in treatment is reducing the inflammatory response through rest and ice massage, use of anti-inflammatory medications, physical therapy modalities and possibly local corticosteroid injections under ultrasound guidance into the tendon sheath. Changes in mechanics relate to potentially using a smaller handle, using thumb on top grip to reduce the stress on the tendons, possibly changing sides on the boat.
Initially time out of the boat is between 1-2 weeks, and cross-training can be used in this period.
Forearm compartment syndromes are the most common forearm pathologies encountered by the rower. This condition relates to a swelling effect of the flexor muscles of the forearm that compresses the neurovascular bundle in the forearm. This creates pain and swelling in the forearm that worsens with rowing and reduces upon cessation of rowing.
Lateral epicondylitis (tennis elbow) may also be common in the rower due to the repetitive nature of the wrist extension whilst in a pronated position. The pain is focused on the lateral elbow at the origin of the extensor tendons. The pain generally increases with feathering of the handle, also at the catch and release phase of the stroke. Pain tends to increase with premature elbow flexion. In this position the extensor tendon passes over the head of the radius, a structure which is more prominent in forearm pronation positions. The tendon then rubs and compresses the tendon in this position.
The cause of compartment syndromes also relates to the grip position on the handle. Excessive feathering and too tight a grip will increase the usage of the forearm muscles and this may quickly increase the compartment pressure in the forearm muscles. Furthermore, novice rowers in growth spurts (teenage rowers) may experience sudden muscle hypertrophy in the forearm flexors and this may accelerate a compartment syndrome.
Direct treatment of a compartment syndrome involves massage and soft tissue release to the muscles and fascia compartments in the forearm. If this fails then surgical release may be necessary.
Management of tennis elbow requires strengthening the extensor muscles in an eccentric fashion and stretching the extensor muscles. Using a lighter grip and possibly a tennis elbow strap may help at this stage.
The primary pathology related to the shoulder include subacromial bursitis and impingement syndromes. This is related to mechanical injury to the subacromial tissues such as the bursa, the supraspinatus tendon and the long head of the biceps tendon.
The predisposing mechanical factors include :
1. Poor scapular mechanics. Limited scapular retraction and being positioned in excessive downward rotation at the catch phase of the stroke.
2. Poor trunk control. Inability to maintain a neutral spine will lead to a flexed posture at the spine. This then mechanically forces the scapula into protraction and excessive shoulder flexion.
3. Shoulder laxity/undiagnosed instability. Increased laxity in the shoulder will lead to excessive shear of the humeral head in relation to the glenoid socket ‘loose ball in socket’. The jolting and jarring of the humeral head can lead to compression of the soft tissues and shear forces across the gleno-humeral joint.
4. Over-reaching at the catch. This creates excessive shoulder flexion, potentially increasing the compressive forces on the subacromial structures.
5. Lunging at the catch. This will create the same pathomechanic as the over-reaching issue.
1. Relative rest to allow the subacromial tissues to settle.
2. Initially ice and NSAIDs if the tissues are inflamed.
3. If this fails, cortisone injection may be necessary.
4. Loosening of tight scapular structures such as the pectoralis minor and shoulder rotators such as the infraspinatus.
5. Strengthening of scapular stabilisers such as the serratus anterior, lower trapezius.
6. Stroke correction. Avoid over-reaching at the catch and maintain a stable upright posture at the catch. If the rower is a sweep rower, then it may be necessary to change sides periodically to de-load the subacromial structures.
Costochondritis is an inflammation of the rib to cartilage attachment. Pain is usually sudden onset and may be associated with clicking and popping.
Rib stress fractures are usually incurred as a result of the muscle attachments onto the ribs. The repetitive pull of the muscles may stress the rib attachment and result in the development of a stress fracture. Often these are misdiagnosed as intercostal strains. They are characterised by achy rib pain that is often insidious in nature that progresses to a sharp pain, including pain with cough, deep breathing or sneezing, regular activities of daily living such as lifting, carrying and rolling in bed and increased pain at the catch or finish of the rowing stroke.
Stress fractures may be precipitated by intense periods of training, low stroke rate training that requires more force on each pull, long rows and ergometer sets, transition to race pace training. The injury is essentially an overload injury of the rib, usually at the insertion of the serratus anterior in the mid-axillary line.
Standard investigations for stress fractures include bone scan (which is usually positive within 48 hours), MRI imaging which will show early bone oedema. Often CT scan will miss the initial onset of stress reaction and bone oedema. Earlier diagnosis results in less time away from rowing.
Development of stress fractures usually require a period of modified activity and rest from rowing until minimal pain. This usually takes 2-3 weeks for the rower to be comfortable with activities of daily living. Whilst resting the rower will need to maintain CV fitness with cross training such as bike/cross trainer/running. Gradual return to rowing volume can be started on a rowing ergometer with low resistance and high stroke rate, and slowly progress to on-water training.
Patellofemoral issues are the most common forms of knee pain to affect the rower. The compression of the posterior patella onto the femur creates an overload to the patellofemoral joint that wears down the cartilage and can create fibrillation of the cartilage and eventual wearing down
of the cartilage to the bone. This results in pain behind the knee and a within-joint swelling.
The natural congruency between the patella and the groove in the femur (the trochlear groove) is affected by tightness in lateral knee structures and weakness in the supporting medial structures. This imbalance allows the patella to be pulled laterally against the bump on the lateral condyle and this then impacts on the femur at 30-60 degrees of knee flexion. This is the common position of the knee in the power stroke in rowing.
The deep knee flexion positions, with strong quadriceps contraction in the drive phase, creates large compression forces between the patella and the femur. If the patella is not situated within the trochlear groove within the femur, the patella may then ride up onto the lateral femoral condyle outside the trochlear groove. This reduces the surface area in the contact area between the patella and the femur. This may then over time lead to a pathology in the cartilage on the underside of the patella.
1. Flexibility. Improve soft tissue compliance in the tissues that attach to the patella such as the biceps femoris, iliotibial band, vastus lateralis.
2. Muscle control. Hip abductor/external rotation strengthening and VMO strengthening may be necessary to correct the mechanics of the lower limb in the drive phase of the stroke, particularly if the knees are dropping inward on the pull phase.
3. Remove biomechanical load. Avoid the painful ‘arc’ of pain from 30-60 degrees knee flexion. This may require a period of time away from the boat and the ergometer, and avoiding the knee flexion angles with leg press and squats.
4. Avoid over-compression by reducing load on the knee. Lighter loads with less resistance.
5. Modify technique by keeping the feet turned outwards on the foot plate. This will encourage the femur to stay externally rotated and reduce the likelihood of the knees dropping inwards.
1. Muscle strain. The large movers such as the paraspinal muscles and the extensor/rotators such as the quadratus lumborum may be subject to strain pattern injuries with overuse/overload.
2. Disc bulge. Characterised by premature disc desiccation and protrusion.
3. Stress fractures/spondylolisthesis. More common in the teenage rower.
1. Disc bulge. Excessive flexion of the spine and excessive posterior tilt on the pelvis leads to increased disc pressure. The main risk factors in the development of a disc injury in a rower are:
a. Poor lumbar spine strength. Unable to maintain neutral spine at the bottom of the catch which results in the pelvis moving into posterior tilt.
b. Tight hamstrings/adductor magnus. As the hip approaches a hip flexion posture at the bottom of the catch, tight hamstrings/adductor magnus will pull the pelvis into posterior tilt to allow further hip flexion.
c. Low stroke rate and high load on erg. Increased load at the catch increases the initial inertia on the pull. This may pull the spine into positions of flexion.
d. Poor form on weightlifting. Poor pelvic position on squats, leg press, deadlifts and Olympic lifts can also increase the lumbar spine flexion position that also then increases disc pressure.
2. Stress fracture/spondylolisthesis. This is due to hyperextension of the spine at the end of the pull phase.
Investigations for back pain in rowing usually starts with plain films looking at lateral and AP views. MRI will be used in selected cases to assess neural compromise due to a disc bulge. Consider using bone scan with SPECT in younger rowers with extension related pain due to the higher incidence of bone stress injury in the younger rower.
1. Initial management. Reduce spinal loading particularly into spine flexion positions. This may need a period of complete de-load away from any spine flexion or posterior pelvic tilt in the case of disc bulge. Stress responses in the bone and the progressions such as stress
fracture and pars defect will require a formal period of de-loading (usually six weeks) and then a gradual reintroduction
of rowing load.
2. Core stability. Rowers need better than average back extensor strength to hold the spine in neutral throughout the stroke sequence. If strength is poor, then the rower will be unable to maintain neutral spine through the movement.
3. Hamstring/adductor magnus flexibility.
4. Monitor erg loads through drag setting
and length of erg pieces.
a. stroke rate
b. no need for “HEAVY” resistance settings during steady state pieces
c. entering the piece – avoid beginning from a dead stop
d. know drag factor of the specific erg which can be affected by damper or fan setting dirt (alters the drag factor).
Rowing is a sport that imposes a high musculoskeletal stress on the body due to the nature of the rowing action and the intense on water and off water training encountered by the elite level rower. The common sites of injury such as the knee, back, ribs, shoulders and forearms/wrists are the reasons why rowers tend to be high users of the medical/recovery services of a sports medicine program. Preventative measures such as regular screening for range of motion faults in hip joints, lumbar spine range of movement and stress testing ribs are common place in the preparation of the rower. Judicious use of off water gym training, particularly dumbbell and single limb training in the sweep rower are needed to ward off common muscle imbalances encountered due to the unilateral nature of sweep rowing.
Smoljanovic´ T., Bojanic´ I., Hannafin J. A., Hren
D., Delimar D., Pec´ina M. (2009) Traumatic and
overuse injuries among international elite junior
rowers. American Journal of Sports Medicine,
37 (6). pp. 1193-9. ISSN 0363-5465