NSAIDs for Exercise: Are You Taking a Risk?

Posted on April 30, 2017 by rbtahmad

Non-steroidal anti-inflammatory drugs (NSAIDs) are a group of drugs designed to reduce pain and inflammation as well as to lower body temperature. Whether you have had a headache or a mild fever, you have probably taken an NSAID before. Many exercisers opt to use NSAIDs in order to provide pain relief. The most common NSAID used by people who exercise is ibuprofen (Motrin or Advil) which provides short-term relief in pain and inflammation. NSAIDs have been shown to help relieve pain and inflammation due to exercise, but there is debate on whether or not the drug should be used to prevent pain due to exercise. To look into this debate, let’s first get an idea of how the drug works.

These drugs work by blocking cyclo-oxygenase (COX) enzymes. These enzymes are involved in producing chemicals called prostaglandins which have various functions in the body. Both the COX-1 and COX-2 enzymes produce prostaglandins that are associated with pain, inflammation, and fever. The common side-effects observed with NSAID use is with the additional effects of blocking the COX-1 enzyme. These enzymes allow for the production of prostaglandins associated with protecting the lining of the gastrointestinal (GI) tract as well as activating blood platelets associated with clotting. By blocking the COX-1 enzyme, complications within the GI tract can potentially occur such as stomach ulcers and temporary intestinal leakage. These side-effects are usually not observed when one occasionally uses NSAIDs, but what if one regularly uses NSAIDs while exercising?

A study published in the 2012 edition of Medicine & Science in Sports & Exercise looked into this potential factor. The study compared nine healthy men at four different time points to see if a combination of high intensity exercise and taking ibuprofen can increase temporary damage to the small intestine. This was after completing a previous study where they concluded that high intensity exercise leads to temporary small intestine injury. The four time points were 1) cycling at high intensity for one hour with 400 mg of ibuprofen in their system, 2) cycling at high intensity for one hour with no ibuprofen in their system, 3) staying at rest with 400 mg of ibuprofen in their system, and 4) staying at rest with no ibuprofen in their system. At the end of each time point, the researchers analyzed the blood of the subjects for levels of intestinal fatty acid binding protein (I-FABP) which is an indicator of injury to the small intestine. They noticed that there was a significantly higher level of I-FABP present in the blood of the subjects who cycled and took ibuprofen compared to the other three groups and that the I-FABP levels were high for as long as 2 hours post exercise. These results show that taking NSAIDs during exercise may be detrimental to the body, especially since many endurance athletes exercise for longer than one hour and may actually consume more than 400 mg of ibuprofen prior to or during their exercise.

Besides the known side-effects, research has shown that there may be a few hidden side-effects by taking NSAIDs with exercise. A paper published in the 2009 edition of the British Journal of Sports Medicine analyzed these potential side-effects. The paper states that taking NSAIDs prior to exercise may negatively impact the musculoskeletal system by masking the pain one feels and potentially causing an injury to inadvertently get worse. The paper also states that prostaglandins are associated with the production of collagen which is an important building block needed for muscle, tendon, ligament, and bone recovery. By blocking the COX enzymes, prostaglandin production decreases causing a decrease in the production of collagen. As the author states, a decrease in the production of collagen may result in adverse effects such as the inability of healthy tissue to adapt to increased loads or a decrease in the rate of collagen regeneration after injury. These effects may lead to an increased risk of injury as well as a delay in recovery after injury.

After reading through these two papers, I found a few limitations. In the first paper, a limitation I found was that they only tested male subjects undertaking endurance exercise. I wonder if there are any adverse effects of taking NSAIDs while performing resistance exercises and if there are any differences between males and females. In both papers, a limitation I found was that they only tested NSAID use prior to exercise. From past experience, I have occasionally used NSAIDs a couple hours after exercise to reduce excruciating pain that had already developed. After taking the drugs, I was pain-free and felt no side-effects. It would be interesting to see whether or not the risks discussed are also associated with taking NSAIDs after exercise if the pain has not already developed.

Overall, it may seem tempting to take NSAIDs to prevent pain due to exercise, but it may not be the ideal thing to do. Although NSAIDs can help you relieve pain, research shows that there are a number of additional risks you may be taking by using these drugs to prevent pain either prior to or during your exercise. If you want to manage pain during exercise, I would recommend just dealing with the pain or maybe looking into non-NSAID drugs such as acetaminophen (Tylenol) which provides pain relief through a different mechanism. If you want to take NSAIDs after exercise, it would be best to use the drugs only when pain has already developed instead of using it to prevent potential pain. It would also be best to use the drugs occasionally in order to prevent an additive effect of the side-effects on your body. But remember, it is always best to talk to a health care professional prior to making decisions regarding your health.

Recommended Further Reading:

Nonsteroidal anti-inflammatory agents

Cyclooxygenase: COX-1 and COX-2 Explained

Aggravation of Exercise-Induced Intestinal Injury by Ibuprofen in Athletes

Exercise-induced splanchnic hypoperfusion results in gut dysfunction in healthy men

Prophylactic misuse and recommended use of nonsteroidal anti-inflammatory drugs by athletes

Questions to Consider:

1.) Have you ever used NSAIDs before? If so, when and/or why did you take them?

2.) If you have taken NSAIDs before, did you use them as a preventive measure or as a way to reduce any discomfort?

How It Works: Isokinetic Dynamometry

Posted on April 26, 2017 by rbtahmad

Using Inverse Dynamics to Prevent Ankle Injuries

Posted on April 7, 2017 by rbtahmad

Identify:

Ankle injuries are one of the most common injuries that occur in NFL linemen. If these injuries persist, the number of games missed can accumulate and the injuries can potentially end a player’s career. Research is currently being done to figure out how these injuries occur in order to design more efficient equipment such as ankle braces and modified cleats. One common method of injury involves the linemen planting the tip of their foot on the ground with great force. The force that is applied translates over to the ankle which causes the injury. Can we use engineering principles to approximate how much force is applied to the ankle? Yes we can, with the use of inverse dynamics. Inverse dynamics calculates forces and moments at one body segment by using the forces and moments of an adjacent body segment as well as the position, velocity, and acceleration of the connected body segments. By using inverse dynamics, one can solve for the amount of force that is applied to the ankles and potentially create new technology, such as insoles for the cleats, which can absorb some of the force that is applied and thus reduce the risk of injury.

Formulate:

Known Values and Assumptions:

Height = 1.956 m (6 foot 5 inches)* → length of foot (d) = (1.956)(0.0425)** = 0.08313 m

Mass = 141.521 kg (312 pounds)* → mass of foot (m) = (141.521)(0.0143)** = 2.024 kg

Force due to gravity (F_g) = m(9.81) = (2.024)(9.81) = 19.855 m/s^2

Normal force (F_N) and force of friction (F_Fr)***, which are applied at the tip of the foot.

Angle between foot and playing surface (θ) = 15°^[1]

Linear acceleration (a) and angular acceleration (α)****

Moment of Inertia (I)

Center of mass = (0.50)(d) = 0.0416 m

*Average height and weight of an NFL lineman during the 2015 season^[2]

**Body segment weight and length^[3]

***Exact value of F_N and F_Fr can be used if force plate data is available

****Exact value of a and α can be used if motion capture data is available

Unknown Values to be Solved For:

x-direction force applied to the ankle (F_{x, ankle})

y-direction force applied to the ankle (F_{y, ankle})

Moment about the ankle (M_ankle)

Equations to be Used:

∑F_x = ma_x

∑F_y = ma_y

∑M = Iα

Figure 1: Free-Body Diagram of the forces acting on the foot and ankle of an NFL lineman

Solve:

Step 1: calculate moment of inertia

Radius of gyration constant for the foot (K_foot)^[4]= 0.475 m

Radius of gyration of the foot (k_foot)= (K_foot)(d)^[4]= (0.475)(0.08313) = 0.0395 m^2

I = (m)(k_foot) = (2.024)(0.0395) → I = 0.0799 kg*m^2

Step 2: solve for forces in the x and y direction

∑F_x = ma_x→ (2.024)(a*cos(15)) = F_{x, ankle}– F_Fr → F_{x, ankle}= F_Fr+ 1.955*a

∑F_y = ma_y→ (2.024)(a*sin(15)) = F_N – 19.855 – F_{y, ankle} → F_{y, ankle}= F_N– 19.855 – 0.524*a

Step 3: solve for moments

∑M = Iα → (I)(α) = M_ankle+ (d_y)*(F_{x, ankle} – F_Fr) + (d_x)*(F_N– F_{y, ankle})

where:

d_x= y-distance between ankle or tip of foot to center of mass

d_y= x-distance between ankle or tip of foot to center of mass

∑M = Iα → (0.0799)(α) = M_ankle+ (0.0416*sin(15))*(F_{x, ankle} – F_Fr) + (0.0416*cos(15))*(F_N– F_{y, ankle})

∑M = Iα → M_ankle=(0.0799)(α) – (0.011)*(F_{x, ankle} – F_Fr) + (0.040)*(F_N– F_{y, ankle})

The solution seems reasonable in the sense that forces are being added on to the ankle. The extent to which the forces are added will depend on multiple factors such as the angle between the cleats and playing surface as well as the height and weight of the athlete being tested. One limitation in this solution was not using exact values of angular and linear acceleration as well as the normal and frictional force. If one is able to accurately obtain these measurements via motion capture and force plate data, they can plug the values into the solutions above to determine exact values of the forces and moments acting on the ankle. For future studies it may be interesting to look at how the other lower limbs, such as the knees and hips, react to translated forces which can accumulate and potentially lead to a greater risk of non-contact injury.

Sources:

[1]: https://www.google.com/patents/US3413737

[2]: http://www.businessinsider.com/nfl-offensive-lineman-are-big-2011-10

[3]: http://www.exrx.net/Kinesiology/Segments.html

[4]: http://health.uottawa.ca/biomech/courses/apa2313/bsptable.pdf

Is There a Way to Improve My Shooting Form?

Posted on March 9, 2017 by rbtahmad

Shooting and training aid for basketball players

Patent Number: US 7442133 B2

Filed on May 19, 2006

Issued on October 28, 2008

Inventor: Jay W. Wolf

Assignee: Star Shooter Company, LLC

U.S. Classification: 473/450; 482/124

14 claims

One of the issues basketball players often face is not having a consistent shooting form. This problem partly occurs due to “off-hand interference”. “Off-hand interference” occurs when forces from the non-shooting hand interrupt the shooting hand when a shot is being generated. Instead of the shooting hand being used to generate a shot, both hands are used which causes an altered shot trajectory. Is there a way to fix this issue? The shooting and training aid for basketball players may provide a possible solution.

This shooting aid consists of three main components. The first component is a band that is strapped onto the non-shooting arm just above the elbow. The second component is a strap with two ends. One end of the strap is attached to the band just above the elbow while the other end of the strap consists of a loop. The loop will be placed on the base of the thumb of the non-shooting hand. The third, and final, component is a second strap. This strap also has two ends. One end of the strap is attached to the first strap at the base of the loop while the other end consists of a pocket. This pocket will be placed onto the middle finger of the non-shooting hand. As the basketball player shoots, the three components will tighten causing the thumb, middle finger, and other three fingers to release from the ball. By releasing the non-shooting hand from the ball, a more precise shot will be created. For a visual representation of the shooting aid, refer to Figure 1 below.

Figure 1: The shooting aid prior to starting the shooting formation (left) and directly after releasing the ball (right).

After the shooting aid has properly been placed onto the non-shooting arm, the basketball player will catch the ball then begin his/her shooting form. Once the arms raise the ball above the head, the three components of the shooting aid will stretch causing the non-shooting arm and hand to tighten. As the arm and hand tighten, the shooting aid will straighten and pull back the thumb and middle finger away from the ball. This will cause the other three fingers to also straighten and be pulled back. The non-shooting hand will then separate from the ball and the basketball player will be able to finish his/her shooting formation.

The engineering behind this device is in the forces that are prevented from being generated. The inventor claims that without using the shooting aid, the non-shooting hand has the ability to generate two forces that can alter a shot. The two forces are from a push in the vertical plane by the thumb and a rotation of the wrist inward in the horizontal plane causing the fingers to drag along the ball. By tightening the non-shooting arm and hand, the device is able to abduct the non-shooting arm away from the basketball as the player shoots so that the shooting arm is only used when generating a shot.

This device would work best for basketball players at any level who want to improve their shooting form as well as their shooting percentages. For example, children who are new to the game can use this device to learn how to shoot a basketball. From past experience, I know how difficult it is to correct your shooting form after initially learning how to shoot in a different way. This device would be beneficial for novices to the game so that they can learn how to shoot properly as early as possible.

This device is novel in the sense that it is one of the few shooting aids that focus on the non-shooting arm. Previous patents have focused mainly on the shooting arm with the goal of teaching basketball players how to follow through with their shot, not on the negative influences of the non-shooting arm. This device is also unique because it is the first shooting aid that prevents the fingers from dragging on the basketball as one shoots. The inventor of this device proposed two other patents in the past that focused on preventing forces by the thumb, but this device combines the previous concept with the concept of preventing the fingers from negatively influencing a shot.

I chose this patent mainly because I play basketball recreationally and have had difficulties in keeping a constant shooting form. It is interesting to see how a slight touch to the basketball from the non-shooting hand can have such adverse effects on a shot. Hopefully this device will help basketball players improve their performance and maybe I could try this device out to see if I can develop a more efficient shooting form.

To read more about this patent click here

BMEG442: Engineering Exercise and Sports

Applying engineering principles to exercise

Author Archives: rbtahmad

NSAIDs for Exercise: Are You Taking a Risk?

How It Works: Isokinetic Dynamometry

Using Inverse Dynamics to Prevent Ankle Injuries

Is There a Way to Improve My Shooting Form?