Calf Strengthening: Rehab, Prehab and Prevention

Calf strains are something we see a lot of in the Physio clinic. They can happen across all age groups but we see an increased prevalence as we age. Why is this? There is some debate as to whether it's age related muscle changes or just that as we age we may do less exercise and more importantly less targeted strength work on our calves there for they are less capable of handling sudden increase in load like sprinting or jumping. Either way prevention is always better than a cure!

Calves are also notorious for recurrent re-injuries. Often, this is due to insufficient time to allow:

a) Natural history of healing to occur

b) Enough time for the tissue to adapt to graduated loading stimulus.

c) Enough progressive loading /overload to facilitate the necessary strength adaptations

Also worth noting, is the importance of adhering to rehabilitation/ return to running/activity timelines. Allowing time and structure to take effect will ensure setbacks are less likely and pain-free activity can resume as soon as it is safe to reintroduce it.

There are three main focuses of rehabilitation following calf strains:

1. Reducing pain and symptoms

2. Progressive loading to stimulate adaptations to the muscle fibres – this period is about rebuilding calf capacity and addressing any imbalances along the kinetic chain

3. Return to running / activity and ensuring the calf has the ability to tolerate the specific demands of the sport or activity you are returning to.

Staging the phase of rehab is contextual to each individual. It is never a one size fits all approach, and is determined by several factors, including but not limited to:

• Pain and dysfunction identified within assessment

• Severity of the injury and location of the injury (ie. muscle, tendon, musculo-tendinous junction, aponeurosis or intramuscular tendon)

• Stage of tissue healing of the injury

• History of similar or recurrent episodes

• Exercise history and current condition of athlete

• Timeline and goals - where in the season/ training regime is the athlete? i.e. are they toward the end of season finals in football, is it their pre-season of netball, are they in the lead up to a half marathon event?

• Any dysfunction up or down the kinetic chain (ie. hip or ankle) that will alter load and tissue response to injury site

This is why a goal-based approach to progressing rehab is better than a time- based approach. Not everyone will hit functional and strength targets in the same timeframes so progressing rehab when someone demonstrates that they are capable of it is preferable to progressing based on dates or time post injury.

STAGES OF REHAB:

Early Stage Rehab

Depending on pain and level of dysfunction, an athlete may be prescribed low loading or isometric exercises in the beginning. An isometric exercise is an exercise where the length of the muscle remains unchanged through range of motion whilst is it held for a duration of time. Isometric exercises early in rehabilitation can be beneficial for:

• possible analgesic effects if tendon related pain is also present

• to enable loading to damaged tissue without stretching or lengthening the healing tissue in the acute phase

• to encourage increased motor unit recruitment of muscle fibres that are inhibited by the brain due to painful stimuli. This enables more of the muscle tissue to be active and exposed to stimulus as athlete is progressed through stages

Examples of isometric calf exercises include double leg calf raise holds, single leg calf raise holds, soleus wall sits, tip toe walking.

Once isometric loading is comfortable, walking is pain-free and symptoms are well controlled, exercises will typically be progressed through range of motion targeting both concentric (shortening phase of contraction) and eccentric (lengthening phase of contraction) ranges to strengthen the muscle through its full-strength curve and full joint range of motion.

This is also a great time to work on other areas of the kinetic chain that are dysfunctional that do not directly load through the injured area, so movements can be integrated functionally into middle and late-stage rehab where sports specific movements are programmed. For example, core/hip strength, knee strength, ankle stability and balance/proprioceptive exercises.

Middle Stage Rehab

During this phase of the rehab, we will aim to challenge the tempo, range of motion and pliability of the tissue through several weeks. This is also the phase we will integrate exercises that are functional and challenge the kinetic chain / replicate demands of the sport/activity relating to athlete’s goals. Some ways this is achieved include:

• Changing the time under tension – typically lengthening the duration of the muscle contraction to expose the muscle to greater tension for longer. This stimulates both muscular and nervous system responses.

  • For example, 3-1-3-1 tempo calf raise – where exercise is performed by 3 seconds concentric, 1 second pause at top, 3 seconds eccentric, pause at bottom for 1 second.

• Increasing the range of motion further to meet functional demands

  • i.e. calf raise off step where strength is challenged through greater range of motion at the bottom of the movement

• Changing the tempo of the contraction – the speed at which force is generated

  • i.e. fast concentric, pause, slow eccentric

  • keeping with calf raise example, exploding to top of movement, pause and lowering slowly back down to starting position

• Adding plyometric exercises which challenges tendon stiffness and is functionally relevant for running and impact based athletes / sports.

  • i.e. pogo jumps, skipping, forward hops which may be prescribed on time basis or a repetition basis

• Kinetic chain involvement: where movements become more functionally meaningful and link together the kinetic chain in preparation for sports specific exercises

  • i.e. front foot elevated split squats, runner box step, triple extension wall marches or sled push

• This is also the phase where running based drills may also be introduced to prepare athlete for return to running program

  • Drills can include: A-Skips, B-Skips, Shuttle Runs and curved running drills.

Return to Running:

• Should only occur when adequate strength and function have been demonstrated in previous stages.

• This will often be in addition to rehab specific exercises/days.

• Running will typically be prescribed as 2-3 runs on non-consecutive days.

• These are often incremented within a shuttle running structure to allow tissue to build up capacity and load exposure. The focus initially is often around time and volume as goals. i.e. 30 seconds running 60 seconds walking x10

• Running speed is typically the last factor to be reintroduced due to the demand on the calf musculature and risk of symptom provocation/set back. One desired volume is achieved, speed may be reintegrated back into sessions, when we are comfortable the tissue has reached relative robustness to tolerate it.

Things to consider along the way that can often affect progress on calf recovery:

• Avoid over stretching – especially when injured tissue is healing. This can lead to disruption of the new tissue that is being laid down and in the case of tendon injuries like the achilles - over stretching reduces tendon stiffness and increases tendon compliance which is the opposite of what we want in a healthy tendon! This is why isometric exercises are often introduced first/in the acute phase so we are not working against the body’s natural healing processes.

• DO NOT avoid strengthening exercises! Completely de-loading calf / lower limb complex in time of injury should be restricted to nor more than the first few days if required. Reducing activity whilst sore, skipping the middle step and then returning to running without addressing the deficiencies will only lead to recurrent re-injury down the line. Having a tailored rehab program will help avoid this pattern and streamline your return to running/activity

• DO NOT underload.... Adding weight to rehab exercises can seem scary but not progressing exercises with enough load or stimulus to allow for adequate loading to meet the demands of activity is associated with higher re-injury rates or causes overload of other areas that need to compensate. Ensuring your program is designed to progressively overload your calf complex to allow adaptations great enough to withstand the activity you are trying to return to is incredibly important. This is how we build robust and resilient muscles.

• Calf strains aren’t always driven from the calf muscle. Keep in mind, there are other structures and injuries that can present or feel like a calf strain, such as neural irritation from the lumbar spine or tendon/connective tissue disorders. Different causes need different approaches to treatment and rehab planning. It is important to have any injury assessed and diagnosed by a healthcare professional so you can ensure you are treating the appropriate driver of your pain/injury.

Consult with your Physio to ensure your calf injury is assessed to identify where your specific pain is coming from and to ensure your tailored loading program meets the demands of the activity you are wanting to return to. This will also ensure you are targeting the whole kinetic chain and reducing risk of injury elsewhere too.

Please note that any advice or exercise recommendations provided here are general in nature and may not be appropriate for every person. If you are experiencing calf pain or reduced strength and function then book into see us at Evolved Physio or see your health care professional for an individual assessment and tailored rehab plan.

Evolved Physio is a welcoming Physiotherapy clinic located in Kincumber on the NSW central coast. Our experienced physiotherapist specialises in the treatment of musculoskeletal injuries. With a background in exercise science, Sally is an expert in incorporating strength based rehab training into your injury programs.

References:

Counsel P, Comin J, Davenport M, et al. Pattern of fascicular involvement in midportion Achilles tendinopathy at ultrasound. Sports Health. 2015; 7:424–8.

Green, B., & Pizzari, T. (2017). Calf muscle strain injuries in sport: a systematic review of risk factors for injury. British journal of sports medicine, 51(16), 1189-1194.

Hébert-Losier K, Wessman C, Alricsson M, Svantesson U. Updated reliability and normative values for the standing heel-rise test in healthy adults. Physiotherapy. 2017;103(4):446–452. doi:10.1016/j.physio.2017.03.002

Hreljac A. Etiology, prevention, and early intervention of overuse injuries in runners: a biomechanical perspective. Phys Med Rehabil Clin N Am. 2005;16(3):651–vi. doi:10.1016/j.pmr.2005.02.002