Calf Strength Goals for Runners Part 2: Strength, Length & Function
Updated: Feb 23
My goal is to empower you to take accountability for your running health. By providing you with the tools and knowledge required to learn how to test yourself and compare your scores to the wider population, we are able to work together to keep you on your feet for longer. This series is all about calvies. What they are, what they do (what don't they do....swoon), and how you can get the most out of them. In part 2 you will find what is considered 'normal' for calf strength, length, and function, and then why we want to smash through the upper limits of normal to best support the fun stuff that we do. Onwards.
We will start with a very brief recap of specific calf strength goals. 2-2.5 x body weight is an ambitious goal, so I have further broken this down to show you how you can work towards it. Ultimately, the most important aspect is not the end result of moving twice your body weight on one leg, but progressively increasing your strength towards the goal. An improvement in your strength of 10% will reduce your risk of injury by 4% (1). This might not sound like much, but if you can improve your single leg calf raise from 20 reps to 22 reps, that reduces your injury risk by 4%. By further increasing your strength to say 30 reps would then result in 20% injury prevention. That's a good deal! For further information and to clarify any technical jargon, check out Part 1 in this series.
Specific Calf Strength Goals for Runners
Classifying runners is very tricky, but this is just a guide so choose what is most appropriate. If in doubt, aim high. All figures below are single leg.
Recreational Athletes (running 2-3 times per week)
Straight leg calf raise: 1.5 x body weight
Seated Smith machine calf raise: 1 x body weight
Seated calf machine: 0.25 x body weight
Single leg calf raise test: 25+ each leg
Training Athletes (typically building towards a goal, run most days, occasional intervals)
Straight leg calf raise: 2 x body weight
Seated Smith machine calf raise: 1.5 x body weight
Seated calf machine: 0.5 x body weight
Elite / Sub Elite Athletes (those that perform sprint intervals & high mileage)
Straight leg calf raise: 2-2.5 x body weight
Seated Smith machine calf raise: 1.5-2 x body weight
Seated calf machine: 0.75 x body weight
2 to 4 years. Yep, that's what I would be considering a normal amount of time to achieve 2-2.5 x body weight straight leg calf raise and 1.5-2 x body weight seated calf raise. Does it matter if you don't achieve these numbers? NO WAY! Remember, progress is positive.
Straight Leg vs Bent Knee
Ideally you would do both...preferably with a Smith machine instead of a seated calf raise machine as the forces are more comparable between machines. For your reference, a seated calf raise machine pretty much doubles the difficulty (check out the numbers above). However I am a huge believer in making strength accessible and time efficient and performing 3 sets of each to fatigue is a solid 30 minute workout. So, how can we get the best of both worlds?
Quick Muscle Overview
The gastrocs have reduced ability to generate force when the knee is flexed, whereas the soleus is active in both a bent knee and straight leg position. Performing the exercise 2 different ways may place different stress through your Achilles, which is important to maximally protect against tendon injury (2, 3). If you are recovering from an injury and your therapist is asking you to perform 2 different kinds of calf raises, this is why. If you have an imbalance in strength between bent knee and straight knee calf raises, then this is something that you must address. It is important to strength train your soleus and gastrocs independently to ensure there are no leaks in the chain. If you have been injured it is likely that you will have an imbalance between legs and also between the function of your calf muscles. Please follow the advice of your therapist as restoring any imbalances will work wonders for your running.
Soft Knee for Time Efficiency
For those without injuries, I would encourage you to test yourself to see what your 5 rep max is on each leg both with a straight leg and bent knee to measure your baseline. If you are well-balanced, then continue to progress your strength with a 'soft knee', not straight, but not at 90 degrees. The challenge is controlling this angle at your knee without performing squats. If your quads are burning, then check your form. This will target both your gastrocs and soleus and free up some time for other exercises. You can vary the angle at your knee each month to make sure you don't neglect any aspects of your calf strength.
Ankle Flexibility with the Knee to Wall Test
Strength and length is the key, with a healthy balance of dynamic muscle power and function. The common considered measure of healthy ankle flexibility is >10cm achieved with the knee to wall test (4). You can also use an inclinometer and measure the ankle along the front of your shin bone and this should be 36 degrees or greater (4). Of course, it is not possible to state that one number suits all individuals, but this should be considered as part of a healthy series of assessments.
The Square Hop Test as a Measure of Calf Function
The square hop test measures dynamic calf function over 30 seconds and includes elements of power and proprioception / balance. Landing within a 40cm x 40cm grid takes a little practice, but any deficits will show up pretty quickly. Every time you land counts as one point, and every time you land on a line, you subtract a point. Count out loud and have someone else call you out on those 'foot faults'. (5)
By increasing your tissue tolerance, you are protecting against risk of injury. Strength is not likely to change running mechanics but instead serves to raise the the tissue capacity ceiling. This allows you to run at a lower % of your total capacity for longer. Check out the full range of strength training programs for runners right here. Please get in touch with any questions.
1. Lauersen JB, Andersen TE, Andersen LB. Strength training as superior, dose-dependent and safe prevention of acute and overuse sports injuries: a systematic review, qualitative analysis and meta-analysis. Br J Sports Med 2018; 52:1557.
2. O'Neill S. A biomechanical approach to Achilles tendinopathy management. Leicester Theses PhD.
3. Grigg NL Wearing SC O’Toole JM Smeathers JE. The effect of exercise repetition on the frequency characteristics of motor output force: Implications for achilles tendinopathy rehabilitation. J Sci Med Sport. 2013
4. Konor M, Morton S, Eckerson J, Grindstaff T. Reliability of three measures of ankle dorsiflexion range of motion. Int J Sports Phys Ther. 2012;7:279–287.
5. O’Neill S Watson P Barry S. Plantarflexor muscle power deficits in runners with Achilles tendinopathy. Br J Sports Med. 2014;48(A49)
6. Haitz K, Shultz R, Hodgins M, Matheson GO. Test-retest and interrater reliability of the functional lower extremity evaluation. J Orthop Sports Phys Ther. 2014;44(12):947-954.