Friday, December 1, 2017

Cycling to Strengthen Knee Following Surgery

Cycling is a great way to strengthen your knee and get back into shape following surgery. A rehab program must strengthen the leg muscles while also reducing the stresses placed on the ligaments and other structures of the knee. Bicycling is a non-weight-bearing, low-impact, controlled exercise that increases the knee’s range of motion, making it one of the most common exercises recommended by orthopedic doctors after knee injury or surgery. The circular movement also nourishes the knee’s cartilage, contributing to the healing and recovery process (1).
Biking strengthens the leg muscles, particularly the quadriceps, hamstrings and calf muscles, which reduce weight and pressure at the joint as stronger leg muscles are better able to absorb the forces encountered during daily activities. Strong leg muscles will protect an existing injury and reduce further injury. Cycling can be nearly as effective as weightlifting in increasing muscle strength while placing less stress and strain on the joint.

A cycling rehabilitation program should follow a systematic progression of increasing resistance levels that keep the knee pain-free (2). Start out slowly and gradually increase the resistance on a stationary bike or progress from riding on flat surfaces to climbing hills or interval training on a road bike. Increasing training volume and intensity too quickly can stress the knee joint and negate the benefits of cycling. Also, avoid standing up on the pedals as this puts too much stress on an injured knee.

Proper fit and positioning on the bike is essential to avoid stress on the joint, which can cause further injury (3). The saddle height should be adjusted so that the knee is bent approximately 25 degrees when the foot is at the bottom of the pedal stroke, and when the pedals are level, the center of the knee joint should be directly above the axle center of the crank arm (4). Additionally, you should be able to comfortably stand over the top tube with your feet flat on the ground.

Whenever possible seek professional advice. Personal trainers and coaches frequently work in cooperation with physicians and physical therapists to develop safe and effective knee rehabilitation programs. Most bike shops can help you find the right bike and make the necessary adjustments to ensure a proper fit. And finally, cycling clubs offer a community of athletes who have experienced similar challenges and can support you in your efforts.


(1) “Cartilage Health - Cycling for Knee Rehabilitation”

(2) The Physician and Sports Medicine: Knee Pain and Cycling, Vol. 32, No. 4, April 2004

(3) W.D. McLeod, T.A. Blackburn, “Biomechanics of Knee Rehabilitation with Cycling,”
The American Journal of Sports Medicine, 8(3):175-80.

(4) How to Set Up a Road Bicycle

Saturday, November 18, 2017

Systems Approach to Fitness Training

Today, I am going to try something a little different. I am going to mix elements of my work and training as a scientist with my approach to training for sports. I am proposing a “systems” approach to training and physical fitness.

What is a “System”?
Incose (the International Council on Systems Engineering) defines a “system” as a construct or collection of different elements that together produce results not obtainable by the elements alone.

How does this apply to the Human Body, and more specifically, to Personal Training?
A system is simply a group of elements, connected by relationships and paired with a purpose. These elements can be visible and physical, but they can also be intangible, and they are held together by relationships. Within the human body system, for example, the relationships connecting the elements are metabolic processes and chemical reactions, as well as our attitudes and emotions. Feedback is key to all systems.

People often assume that if running 5 miles per day, 5 days per week, helps them to lose 10 pounds a month, then running 10 miles per day, 5 days per week, should help them to lose 20 pounds per month. However, the body (and other systems) don’t necessarily operate that way. The excess mileage can contribute to injury, fatigue, and general burnout syndrome. Our bodies may not be capable of handling this much.

What is the Solution?
Since we cannot fully understand our system (our body), predict its behavior, or have control over it, we must study its behavior and the patterns it exhibits. This will enable us to help our body to function better and to identify when we have a broken system that needs repair.

How do we do this?
We need do this by keeping a training log so that we can better understand how various factors influence our bodies. It is important to pay attention to factors that are both measurable and immeasurable. Humans tend to place more emphasis on quantifiable factors and less on qualitative factors because it is easier to measure and relate to a quantity. However, tracking your level of physical fatigue and personal well-being is just as important as tracking your weight and the number of miles you have run. By tracking all factors, in combination, you can optimize your system (your body) to maximize your performance for whatever your purpose might be: weight loss, success in a 10K race, or other.

Feedback is key to all systems. For personal and fitness training, training logs provide that feedback. 


Finding Your Optimum Sport

If you are participating in a sport for fun and enjoyment, then do what makes you happy, do what you love. However, for many people, being happy means participating in a sport that suits them best, one in which they can excel. And for those individuals, I will offer some suggestions today for choosing the optimum sport based on your physiology, which is largely influenced by your genetic makeup. To determine the sport in which you may excel, examine your physiology and that of your biological parents and siblings. Are members of your family tall or short, slim or stocky, muscular or scrawny? Hard work and training are crucial to any sport; however, this will get you only so far. Our genes largely control our physical attributes.

This is going to seem obvious, but if you are very tall, you are best suited for basketball. 17% of American men aged 20 to 40 that are over 7-feet tall are in the NBA. Shorter-than-average NBA players usually have other traits that compensate for their height. For example, Spud Webb, who is only 5’7”, has long, stiff Achilles tendons that allow him to jump high. Also, shorter NBA basketball players usually have longer arms, which give them a greater reach.

Distance Running (and Endurance Sports)
Long-distance runners, such as marathoners, have long legs, slim torsos, and small bodies. Long legs give a person a longer stride and a faster top speed, and slim torsos are lighter and produce less load on the legs. The longer your legs, the better you tend to be at running longer and longer distances. And a smaller body means there is a larger skin surface area to body volume ratio, which allows the body to disperse heat more effectively. This is crucial in endurance sports, such as distance running.

Successful distance runners also have a higher percentage of slow-twitch muscle fibers. The average person has a 50-50 mix of slow-twitch and fast-twitch muscle fibers. However, it is not uncommon for marathoners to have over 75% slow-twitch muscle fibers. Slow-twitch fibers have a slower response time and provide us with the endurance we need to run long distances. You can be tested to find out your precise mix of muscle fibers. However, you can figure it out for yourself, based on how quickly you develop muscle, for example. If you develop muscles quickly, you have more fast-twitch fibers. If you have trouble developing muscles, you likely have more slow-twitch muscle fibers.

Sprinting (and Fast-Action Sports)
Shorter legs are better suited for sprinting because short legs have less inertia, enabling them to accelerate quickly from a standing start. Leg length seems to be correlated with the runner’s optimum race distance, as I alluded to above. For sprint distances, the shorter your legs, the shorter the distance at which you will be most successful. In the NFL, for example, where quick acceleration is needed, running backs and cornerbacks tend to be short. And whereas the height of other NFL players has been on the rise, the height of running backs and cornerbacks has been steadily decreasing over time.

Sprinters also have a higher percentage of fast-twitch muscle fibers. Olympic-level sprinters generally have at least 75% fast-twitch muscle fibers in their calves. Fast-twitch muscles respond very quickly and are good for sports that require fast, explosive movements, such as sprinting and weightlifting.

Successful swimmers also have short legs, as well as long arms and long upper bodies. Olympic swimmer Michael Phelps is 6’4”, but he has very short legs. Despite being 6’4”, he wears pants with a 32-inch inseam!

Today’s blog was not meant to discourage anyone from pursuing the sport of their dreams, but rather, it was meant to help you optimize the sport, or even the position that you play, within a particular sport. For example, when I was younger, I played soccer. My short, muscular legs were best suited for explosive bursts of speed, so I often played right-forward where I was able to sprint to the far corners of the field with the ball and set up great plays for other players. I really enjoyed playing a sport that I was good at. 

When I got a little older, I began training for marathons and endurance races. Okay, I’ve probably lost half of you right about now. Well, as I grew older my goals changed. I knew I would never win a marathon because it is physiologically not possible. However, I was only competing against myself. It was not that important for me to win a race or to even place in my age group. I just wanted to see what I was capable of accomplishing. 

So, please use the information provided here as a starting point to determine what physical activity might be the most rewarding to you. We generally stick with things that we are naturally good at. The important thing is to get some type of physical activity every day because it is so important to a healthy body and a healthy mind.

For more information on how genes affect your suitability in different athletic endeavors, I encourage you to read “The Sports Gene” by David Epstein. It goes into much more detail than what I provided here. Epstein even discusses how motivation level and sensitivity to pain are affected by our genes and can impact our success in sports.