Trikke Surface electromyography (SEMG) Report
Prepared by: Dr. Kathy Ermler - Dr. Mike Butler - Dr. Paul Luebbers
All testing was done with a Noraxon Myotrace 400. Which is a portable surface electromyography (SEMG), which is used to detect the electric activity of a muscle. Electrodes were placed on the skin directly on the muscle belly and parallel to the grain of the muscle fibers.
Summary of Findings
It must be stated that the statements below are based on the initial findings of SEMG testing on Trikke riding. A lot of questions arise from the findings, but it can show us the specific muscle usage at a specific riding styles. More intesive testing is necessary to give a full and detailed report on the muscle activity and Trikke riding.
The parts of the body that are most used for the following types of riding:
- Arms Easy – Arms, shoulders, upper leg and lower leg. The Triceps or the back of the upper arm is particularly active during arms easy. This type of riding would be characteristic of a beginning rider.
- Arms Hard – The arms hard style appears to be a good overall body workout for many muscles in the body. Arms, shoulders, chest, abdomen, buttocks, upper leg, lower leg. The primary muscular activity was in the arms, shoulders, upper leg, lower leg and back.
- Speed – The speed style is very similar to the arms hard style with one exception. In the speed style a rider uses more upper leg (quadriceps and hamstrings) than on the arms hard. This style provides a good overall body workout for all muscles of the body.
- Squat – The squat style is more of an interval style that a riding style. In other words, a person would not set out to ride long distances or for long amounts of time using a squatting technique. However, the rider may use this technique in short bursts during the ride. The primary muscle area that is activity is the quadriceps. This style could be used to put additional stress on the quadriceps during a ride.
- Uphill and Downhill – Not enough data were collected to draw any conclusions about uphill and downhill riding. However, it appears that on the data that were collected, riding uphill greatly enhances the activity of the muscles.
- Cardiovascular benefits –heart rate monitors were used by John and Gildo only one time. Riding the Trikke put both John and Gildo into their target heart rate zones. Research in the past by the University of The Hague and Amsterdam show the energy usage and heart rates at different paces.
Muscles by Style and Rider
Please note the following charts show muscle activity during particular styles of riding. This data must be interpreted with some caution since the muscle activity depicted in the style charts is not necessarily comparable. The bars in the charts indicate the actual microvolts of electrical activity that were detected with the surface EMG equipment. However, a certain level of activity in one muscle only shows the degree to which that one muscle was active.
With this data one can compare the activity of a single muscle or muscle group across the various styles to show which styles evoke the greatest activity in a particular muscle or muscle group. This is presented after a consideration of the muscle activity within each of the selected riding styles.
Trikke riding style Arms Easy
Starting riders use a lot of arm power to create forward momentum. The arms easy style let's the arms relax and use leg power to create forward motion. It's interesting to see that the triceps (back upper arm) is high ranked. Probably because you keep your arms more straight and to keep the elbow from bending you use the triceps. You can also see that the VLO (side upper leg muscle) is being used. So riding without bending the arms is great to train off the excess flab at the upper arm and to focus more on the upper leg muscles.
In the arms hard style, we see again the triceps in the top 5 and this time also the deltoid (shoulder) muscles. Still the legs are used as well since the Vastus Lateralis (quadriceps) is peaking also. It's also interesting to see that the trapezoid (big back muscle) is being used. The trapezoid (trap) muscle is a long, trapezoid-shaped muscle that runs down the upper section of the spinal cord, originating at the base of the skull and attaching down in the middle to lower back. The angles of the Trapezius fibers provide pull in three different directions: up, down and in towards the centerline of the body. By training this musclegroup you are strengthening your back.
Arms Hard riding style video
The speed style is just cruising as fast as you can. Almost all muscles are being used and there are less peaks. You do not isolate a specific muscle group but you use a lot of them enough to call it a muscle training.
Speed Trikke style video
The squad style is all about isolating one muscle group, namely the upper leg muscle. With squad style you ride the Trikke while squatting down. Should you try this, make sure your feet are located in the front of the foot platform. There is an increased chance of tipping over backwards.
No video yet available
As many Trikke riders can tell you uphill is a true challenge both physical as psychological. Don't let the below graph fool you, the "rectus fem" upper leg muscle is very high, but the other muscles are very well trained.
Uphill Trikke riding style video
EMG Results by Individual Muscles
Muscles tested in upper and lower arms include Biceps, Triceps and Brachioradialis
The biceps brachii is an elbow flexor and is more efficient with this motion when the radioulnar joint (forearm) is supinated. Typically, when riding a Trikke, the for arms are pronated, so this position would reduce the amount of biceps participation in the action. In examining the SEMG patterns for Biceps, the biceps are used primarily in advanced types of riding (e.g., speed, punching, pulling squatting). There was no data for John on the biceps.
The primary function of the Lateral Triceps is elbow extension. Based on the SMEG patterns, it appears that the Triceps are the primary muscles to be activated in various types of riding, except for pulling, punching and deep carving. Both John and Gildo have similar activation patterns for the Triceps except for uphill. It appears John is using his Tricep muscles far more on uphills than Gildo. Gildo uses his Triceps more on almost every type of riding other than uphill. This may be one significant difference between efficient and inefficient Trikke riders. Although without further SEMG testing, this conclusion is not based on sufficient data.
The brachioradialis is an elbow flexor. When the forearm is pronated, the brachioradialis is more active during elbow flexion since the biceps muscle is in a mechanical disadvantage. Trikke riding requires the rider to assume and maintain a pronated position. Based on the SEMG patterns, it appears there is a difference in the use of the brachioradialis muscles between an efficient and inefficient rider. The lower arms are not used to any significant degree in any type of riding except uphill riding.
The primary function of the Pectoralis Major is to move the upper arm across the body (transverse flexion). Based on the SEMG, a relatively consistent pattern of use can be seen. It appears that the pectoralis major is activated but at a very low level and does not seem to contribute to the motion of the trikke except when riding up hill or uphill hard.
The Serratus Anterior draws the scapula forward, abducts the scapula and stabilizes the vertebral border of the scapula to the rib cage. Based on the SEMG pattern, it appears that the Serratus Anterior is moderately active in all forms of riding for both.
The function of the Deltoid muscle is essentially to move the arm away from the body. The Anterior head raises the arm away to the front of the body. The Anterior Deltoid is active in all types of Trikke riding; particularly arms hard and uphill riding.
Rectus Abdominus Upper and Lower
The Rectus Abdominus muscle is really one long muscle that runs from the sternum to the pubic bone. It is commonly known as the "six-pack" muscle of the abdominal area. The upper Rectus Abdominus Upper (URA) muscle runs from the sternum to the navel. The Rectus Abdominus Lower (LRA) muscle runs from the navel to the pubic bone. The Rectus Abdominus muscle assists in the flexion of the spine (bringing the rib cage closer to the pelvis or pelvis closer to the rib cage).
In most of the riding styles, there is very little activity in either the URA or the LRA. The greatest activity in the Rectus Abdominus muscle is found in styles that include off Trikke work (e.g., skip jump). The increase in muscle activation in the Rectus Abdominus muscle may be a function of a running motion rather than the action of riding a Trikke. Gildo was not tested on the URA or LRA for uphill.
The External Obliques run diagonally along the trunk. These muscles work to rotate the torso and stabilize the abdomen. According to the SEMG pattern, very little activity is occurring in the External Obliques in most riding styles. This is very surprising considering the rotational aspect of the Trikke motion, this needs retesting.
The Trapezius (trap) muscle is a long, trapezoid-shaped muscle that runs down the upper section of the spinal cord, originating at the base of the skull and attaching down in the middle to lower back. The Trapezius muscle permits scapular elevation (shrugging up), scapular adduction (drawing the shoulder blades together) and scapular depression (pulling the shoulder blades down). Based on the SEMG, John appears to use the Trapezius mucles significantly more than Gildo in all types of riding. This difference could again be the difference between an efficient and an inefficient rider or differences in riding styles between these two riders.
Latissimus Dorsi muscles are the largest muscles of the back and are large, fan-shaped muscles located in the middle of the back. The Latissiumus Dorsi extends, adducts and medially rotates arm. It is difficult to draw any conclusions between the two individuals since no data was taken on John for arms easy, hard, speed and uphill. However, based on very limited data, it appears that the Latissimus Dorsi is used when riding a Trikke.
The Erector spinae muscles run directly down the vertebrae and act to laterally flex and extend the spine. Good to see for Trikke is that it us being used in almost all riding styles but not extremely used. You could perhaps use the Trikke to tighten the Erector spinea muscles and thereby reduce back problems.
The Gluteus Maximus muscle acts to externally rotate and extend the hip. This muscle is the strongest muscle in the human body. No activity was noticed in this muscle in arms easy, arms hard and very little activity was noted in this muscle in the squat or speed riding. This result is mostly likely attributed to the functioning of the SEMG machine and not a result of inactivity of the Gluteus Maximus muscle; although this is to be determined with further testing.
The Gluteus Medius muscle lies partially under the Gluteus Maximus muscle and acts to abduct the hip and rotate the leg medially. In all types of Trikke riding, this muscle is moderately active. The rocking motion of the Trikke would uses abduction at the hip.
Lower body muscles
The Biceps Femoris muscles are located on the back of upper legs. The Biceps Femoris flexes the knee, rotates the tibia laterally; long head also extends the hip joint. The Biceps Femoris were activated during all types of riding for. The greatest activation of the Biceps Femoris occurred during the ski jump and deep carving. Uphill and downhill were not tested.
The Semitendinous is located on the back of the upper leg. It extends the thigh and flexes the knee, and also rotates the tibia medially, especially when the knee is flexed. Similar to the Biceps Femoris, this Semitendinous muscle is activated during all types of riding. The greatest activation of this muscle occurred during the ski jump and deep carving.
The Rectus Femoris is one of four muscles that make up the quadriceps muscles in the upper leg. It acts to extend the knee. This muscle is activated in most types of Trikke riding, but are highly active when riding uphill.
The Vastus Lateralis is one of four muscles that make up the quadriceps muscles in the upper leg. It acts to extend the knee. This muscle is activated in most types of Trikke riding, but are highly active when riding in a squat position or riding downhill.
Lateral and Medial Gastrocnemious
The Gastrocnemious muscle is located on the back of the lower leg. It has two heads; a lateral head and a medial head. Both muscles act as a very powerful plantar flexor of the foot; it also aids in flexion of the knee. It appears that Gildo’s riding style allows for more activation of the Gastrocnemious muscle than John’s riding style. Gildo uses a plantar flexion motion to move the Trikke, while John remains more flat footed doing the ride. So finishing your power stroke on your toes gives a better workout.