cadence | Garrett McLaughlin, MS, ATC, CSCS, ART

| Article written on March 7th, 2020 at 1:17pm | Follow Garrett on Facebook and Instagram |

Anterior knee pain is common amongst runners, athletes, and the general population. In this article, I will attempt to explore different considerations regarding patellar tendinopathy specifically and provide various loading strategies for rehabilitating the knee back to full function.

Click here to connect with Garrett directly about your knee pain.

The patellar tendon is located directly at the front of the knee and connects the quadriceps, patella, and proximal tibia. Pain is usually localized to the inferior pole of the patella and during movements that load the quadriceps. Cook et al reports that approximately 1/3 of athletes who presented with patellar tendinopathy were unable to return to sport for more than 6-months. Therefore, early detection in less severe stages is crucial, as well as the acceptance that resolution of symptoms could take an extended period of time.

Anterior view of the knee joint and patellar tendon.

What’s important to realize about an injury to the patellar tendon is that we are dealing with a dense fibrous connective tissue that connects muscle to bone. According to Thorpe et al, the main function of tendons is to “transfer muscle generated force to the bony skeleton, facilitating movement around a joint, and as such they are relatively passive, inelastic structures, able to resist high forces.” Despite being able to resist against high forces, as in running, jumping, and many sporting activities, tendons are susceptible to injury based on various scenarios…

The force placed upon the tendon exceeds the tissue’s load capacity
A series of small and repetitive forces are applied for a duration long enough to cause tissue breakdown
Other biomechanical factors are creating compensation elsewhere throughout the kinetic chain which ultimately increases load on the tendon

Regardless of which scenario proves to be true, the end goal of any tendon rehabilitation program is not the absence of pain, but return to full, pain-free function. Like with most injuries, rest is important and will allow the injury to calm down temporarily. However, tendon pain will likely resume when load is re-introduced to the area if the capacity of the tissue is not restored.

In the research article, ‘Current Concepts in Biomechanical Interventions for Patellofemoral Pain,’ Willy et al describe a homeostasis model first created by Scott Dye in 2005. This model suggests that the injury process can be stimulated in response to sudden bouts of increased training loads or stressors. For example, a runner or athlete that is conditioned for a specific distance or intensity but decides to increase one or both of these factors before the tendon is ready to handle the increased workload. That’s why I recommend all runners follow a structured and progressive training program which increases mileage in a safe and effective manner to build tissue tolerance.

Willy et al states that once homeostasis of the tissue is disrupted, sudden increases in training loads may no longer be able to be tolerated even if these are routine daily activities. Therefore, once the tissue is in a pathologic state, the ability to load without pain decreases significantly. The goal now becomes to re-establish this homeostatic relationship to stabilize the tissue, then progressively restore the loading capacity to be more tolerant to the forces it will encounter. Basically, excessive loading created this situation but it will also be a key factor in resolving it for long-term success.

Now, before we cover the loading strategies to resolve patellar tendinopathy, it’s important to touch on cadence, aka step rate, and it’s impact on the knee while running. Overstriding (image B below) is a term that refers to the foot landing too far in front of the body’s center of mass at initial contact. What this does is create a braking mechanism and thus increases energy absorbed at the knee.

Progressively loading the quadriceps and patellar tendon will certainly make the area more tolerant to the forces of running. At the same time, increasing cadence by just 5-10% has been shown to decrease energy absorbed at the knee by 20-34%.

Running at a higher cadence reduces stride length, disperses the amount of force over more steps, and allows the foot to land closer underneath the body’s center of mass. A combination of both approaches is important to consider in order to reduce the likelihood of injury and/or return to running following patellar tendinopathy. Click here to read a more in-depth article that I wrote on the topic called, ‘The Impact of Cadence on Running Mechanics.’

When incorporating the following loading strategies, it’s important to keep in mind the 24-hour rule. Basically, you want to stress the patellar tendon in a healthy way that limits pain to nothing above a 3 out of 10. And if pain lingers, it should resolve completely within 24-hours. This is an important concept to understand with tendon pain. A certain degree of pain is acceptable and might be needed to elicit the desired response from the tendon. However, if your pain exceeds these parameters then modifying certain variables, such as the exercise, tempo, load, and position might be warranted.

Decline Squat Progression

The Decline Squat is a fantastic exercise that utilizes a slant board or elevated heel position to increase demand on the knee. Like with all of these progressions to rehabilitate patellar tendinopathy, it’s important to understand the dose and response relationship before increasing the intensity in anyway. What I mean is, start simple and progress slowly after seeing how the tendon responds to the added load, tempo, and number of repetitions. The different variations of this movement allow you to gradually increase load on the knee joint in a progressive manner. In this video, I demonstrate the bodyweight, goblet, and 2-dumbbell Decline Squat progression.

Spanish Squat Progression

The Spanish Squat is a somewhat newer exercise that I’ve only used for the past 2-years or so. Like with all of these progressions to rehabilitate patellar tendinopathy, it’s important to understand the dose and response relationship before increasing the intensity in anyway. What I mean is, start simple and progress slowly after seeing how the tendon responds to the added load, tempo, and number of repetitions. The different variations of this movement allow you to gradually increase load on the knee joint in a progressive manner. In this video, I demonstrate the bodyweight, goblet, and 2-dumbbell Spanish Squat progression.

Lateral Step-Up with Counterbalance

Since the knee is largely influenced by stability at the foot, ankle, and hip, it’s important to successfully complete one of the bilateral exercises mentioned above and then move on to a single leg variation. The Lateral Step-Up with Counterbalance allows the body to be held in a position that loads directly into the knee joint. Like with all of these progressions to rehabilitate patellar tendinopathy, it’s important to understand the dose and response relationship before increasing the intensity in anyway. What I mean is, start simple and progress slowly after seeing how the tendon responds to the single leg position, load, tempo, and depth of the step. This exercise is usually recommended after laying the foundation with the two bilateral progressions demonstrated above.

Despite showing you two different loading progressions to properly rehabilitate patellar tendinopathy, it’s not my intention for you to complete both of these. I would start by determining which is the best starting point for you and following that path to create a more tolerant and pain-free knee. Once that’s achieved, the Lateral Step-Up with Counterbalance is a suitable next step to incorporate single leg loading and stability. This is especially important if your goal is to return to running or a change of direction sport.

I hope this article has helped you better understand patellar tendinopathy, as well as recommended strategies to reduce pain and increase function. As always, it’s important to consult with a trained healthcare professional to be properly diagnosed and understand the underlying factors which may be contributing to your injury. Please take a second to click here so we can create a structured plan to resolve your knee pain once and for all.

By: Garrett McLaughlin, MS, ATC, CSCS, ART

| Article written on February 20th, 2020 at 12:25pm | Follow Garrett on Facebook and Instagram |

Cadence is a hot topic in the running world, and for good reason. When manipulated properly it can positively impact your running to improve efficiency and reduce strain on sensitized tissues. As always when it comes to changing your running form, it’s important to understand the research, seek the guidance of a trained healthcare professional, and do so in the safest way possible. This article will cover some potential benefits that cadence manipulation can have on your running mechanics.

Let’s start by defining cadence… Cadence, also known as step rate or step frequency, is the number of steps you are taking per minute (spm). An easy way to calculate this is by counting the number of steps on your conversational pace run for 30-seconds and then multiplying that number by 2. This number should vary depending on your pace, intensity, and terrain. So keep it simple by calculating cadence during your long, slow distance run first. If you’re fortunate enough to have a Garmin watch or other wearable technology, it’s likely that your cadence has been tracked all along.

Over the years, there has been a lot of debate surrounding cadence. Famous running coach, Jack Daniels, and local running stores who offer Good Form Running Clinics, often propose 180spm as the gold standard. The problem with that number is, it does not take into consideration the unique characteristics of you as a runner, how many steps per minute your body auto-regulates to, and your injury history. When altering running mechanics, it’s important to do so on an individual basis and while considering every variable. This may or may not mean 180spm ends up being the right cadence for you. And, truthfully, there was no mention of this number in any of the research articles I reviewed.

In the following sections, let’s comb through the research to determine how much impact increasing your cadence can have on your running. I will highlight various research articles and discuss the key findings of each. This will serve as a good review of the literature and you can dig deeper into any article that interests you.

Article #1: Influence of Stride Frequency and Length on Running Mechanics by Schubert et al

Objective: To determine how running mechanics change when manipulating stride frequency and stride length.

Findings:

The knee was the most affected joint when cadence was increased, which displayed a more flexed position at initial contact and less peak knee flexion during the stance phase
The ankle demonstrated a more plantar flexed position at initial contact with a higher cadence
The hip displayed less peak hip flexion and adduction during initial contact with a higher cadence
The foot lands closer to the body’s center of mass when cadence is increased
There was a reduction in peak vertical ground reaction forces
There was a reduction in center of mass vertical excursion
Increasing cadence reduces ground contact time which in turn increases leg stiffness

Click here to view this article.

Article #2: Effects of Step Rate Manipulation on Joint Mechanics During Running by Heiderscheit et al

Objective: Assess the biomechanical effect that a 5% and 10% increase in cadence has on the hip, knee, and ankle joints to determine if it is a possible strategy to reduce lower extremity injury rates.

Findings:

Step length decreased as cadence increased
Decreased center of mass vertical excursion
Reduction in braking impulse at initial contact
Foot inclination angle, peak vertical ground reaction force, and step duration only differed with a 10% increase in preferred cadence
Rate of perceived exertion increased when cadence was 10% greater than preferred cadence
A 5% increase in cadence reduced energy absorbed at the knee by approximately 20%
A 10% increase in cadence reduced energy absorbed at the knee by approximately 34%
A decrease in preferred cadence produced a similar increase in energy absorbed at the knee
A 10% decrease in cadence produced a significant increase in energy absorption at the ankle and hip joints, however, a 10% increase in cadence only reduced energy absorption at the hip joint

Click here to view this article.

Article #3: The Effects of Running Cadence Manipulation on Plantar Loading in Healthy Runners by Wellenkotter et al

Objective: Evaluate the effects of cadence manipulation on plantar loading during running.

Findings:

Total foot contact time and peak force were lower with a 5% increase in cadence
Foot contact time was greater with a 5% reduction in cadence
Faster cadence decreased heel loading and did not increase metatarsal loads
Metatarsal loads were generally reduced with an increased cadence
A 5% increase in cadence was shown to reduce plantar loads 2.4-8.0%

Click here to view this article.

Article #4: Leg Stiffness and Stride Frequency in Human Running by Farley et al

Objective: Determine the relative importance of changes to the leg spring stiffness and the angle swept by the leg spring when humans alter their stride frequency at a given running speed.

Findings:

Stiffness of the leg spring increased 2.3x between a cadence that was 26% below preferred to 36% above preferred
The leg spring becomes stiffer to accommodate a faster cadence and less stiff when accommodating a slower cadence

Click here to view this article.

In conclusion, these research articles show there may be merit when manipulating cadence in certain situations. Increasing cadence may reduce overall load into the affected tissue if you are suffering from a running-related injury and improve running efficiency. Using a metronome can be a helpful tool when increasing to 5% or 10% above your preferred cadence as shown in the articles. It’s recommended to not make any abrupt changes, but do so in a slow and progressive manner which will allow your body to adapt to these changes in running form.

If you have any questions about how cadence manipulation may affect your running or you want more information regarding the Healthy Running Program, click here to contact me directly. Thanks for reading!

By: Garrett McLaughlin, MS, ATC, CSCS, ART

Garrett McLaughlin, MS, ATC, CSCS, ART

Browsing Tags cadence

Loading Strategies to Resolve Patellar Tendinopathy

| Article written on March 7th, 2020 at 1:17pm | Follow Garrett on Facebook and Instagram |

Decline Squat Progression

Spanish Squat Progression

Lateral Step-Up with Counterbalance