Surface electromyography (SEMG) Report. Prepared by Dr. Kathy Ermler Dr. Mike Butler Dr. Paul Luebbers

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1 Surface electromyography (SEMG) Report Prepared by Dr. Kathy Ermler Dr. Mike Butler Dr. Paul Luebbers For Trikke Company August 24, 27

2 Trikke EMG Report Testing Protocol All testing was done with a Noraxon Myotrace 4. The Myotrace 4 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 summary that follows is not representative of extensive SEMG testing, but represents the initial findings of SEMG testing on Trikke riding. At this point there are more questions that have been raised than specific answers with regards to muscle activity and Trikke riding. The general findings include: 1. The parts of the body that are most used for the following types of riding: a. Arms Easy Arms, shoulders, upper leg and lower leg. The Triceps or the back of the upper arm is particularly active during. This type of riding would be characteristic of a beginning rider. In this particular riding style, there was a difference between and in the use of various muscles. used his quadriceps (VLO and Rectus Femoris) and Hamstrings (Biceps Femoris) more than. appeared to use his lower legs (Gastracnemius (lateral/medial) muscles more than the his quadriceps or hamstrings. b. Arms Hard The 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 for was in the arms, shoulders and lower leg. The primary muscular activity for was in arms, upper leg and back. c. Speed The style is very similar to the style with one exception. In the style, both and use more upper leg (quadriceps and hamstrings) than on the. This style provides a good overall body workout for all muscles of the body. d. Squat The 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 ting 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. e. Uphill and Downhill Not enough data were collected to draw any conclusions about and riding. However, it appears that on the data that were collected, riding greatly enhances the activity of the muscles. 2. One area of the body that does not seemed to be particularly active during any of the types of rides is the abdominal area. Trikke riding may not provide sufficient work to stress the abdominal muscles. Additional exercises outside of Trikke riding may need to be done to develop the abdominal area. 3. Cardiovascular benefits heart rate monitors were used by and only one time. Riding the Trikke put both and into their target heart rate zones. This is one area that needs to be pursued further.

3 Future questions 1. How do the SEMG patterns seen when riding a Trikke compare to a person s Maximum voluntary contractions? 2. How do the SEMG patterns seen when riding a Trikke compare to the same person running, walking or biking? 3. Is the Trikke effective in improving cardiorespiratory fitness? 4. How do the SEMG patterns of a beginning Trikke rider different from an advanced or intermediate rider? 5. Are the differences noted between and characteristic of an efficient vs an inefficient rider?

4 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. For instance, shows over 8 microvolts (mv) of activity in his triceps during the arms easy style. Also, shows about 3 mv of activity in his brachioradials during the same ride. One may be tempted to conclude that the triceps were over twice as active as the brachioradials while riding in this style since the activity of the triceps at 8 mv is over twice that of the brachioradials at 3 mv. However, these numbers share no common reference. It is possible that the 8 mv in the triceps is less than half of the activity possible in the triceps and that the 3 mv in the brachioradialis indicates a near maximal effort for that muscle. For this reason, strong conclusions based on comparing these numbers should be avoided. This problem can be resolved in future research by using percentages of maximal effort or maximum voluntary contraction (MVC) (a relative measure), which will allow direct comparisons. On the other hand, it is entirely reasonable to 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.

5 Arms Easy In the style, the following muscles were used for and for Ranking (Top 5 muscles used) 1 Triceps Vastus lateralis (Quadriceps) Lateral Gastrocnemius Triceps Medial Gastrocnemius Biceps Femoris Brachioradialis Serratus Anterior 5 Vastus lateralis (Quadriceps) Middle Trapeziod

6 Arms Hard In the style, the following muscles were used for and for Ranking (Top 5 muscles used) 1 Triceps Vastus lateralis (Quadriceps) Deltoid Triceps Brachioradialis Middle Trapezoid Medial Gastrocnemius Deltoid 5 Vastus lateralis (Quadriceps) Rectus Femoris

7 Speed In the style, the following muscles were used for and for Ranking (Top 5 muscles used) 1 Triceps Vastus lateralis (Quadriceps) Rectus Femoris Rectus Femoris Brachioradialis Triceps Serratus Anterio Serratus Anterior 5 Lateral Gastrocnemius Deltoid

8 Squat In the style, the following muscles were used for and for Ranking (Top 5 muscles used) 1 Vastus lateralis (Quadriceps) Vastus lateralis (Quadriceps) Rectus Femoris Rectus Femoris Triceps Serratus Anterior Biceps Femoris Middle Trapezoid 5 Brachioradialis Biceps Femoris

9 Uphill In the Uphill style, the following muscles were used for and for Ranking (Top 5 muscles used) 1 Rectus Femoris Triceps Medial Gastrocnemius Brachioradialis 5 Deltoid

10 EMG Results by Individual Muscles Arms Muscles tested in upper and lower arms include Biceps, Triceps and Brachioradialis Biceps 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 forarms 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.,,, ting). There was no data for on the biceps Biceps Brachi hard

11 Triceps 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, and. Both and have similar activation patterns for the Triceps except for. It appears is using his Tricep muscles far more on s than. uses his Triceps more on almost every type of riding other than. 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. Lat Triceps hard

12 Brachioradialis Brachioradialis 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 of and, 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 riding for but are used relatively consistently across types of ride for. Brachiorad hard

13 Chest Area Pectoralis Major Pectoralis Major 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 between and 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 hard. Pect Major hard

14 Serratus Anterior 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 and. Serr Ant hard

15 Shoulders Anterior Deltoid Anterior Deltoid 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 for both and ; particularly and riding Anterior Deltoid hard

16 Abdominal Area 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., ). 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. was not tested on the URA or LRA for. Rect Abd Upper hard Rect Abd Lower hard

17 External Obliques 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 seems very surprising considering the rotational aspect of the Trikke motion. External Obliques Ext. Obliques hard

18 Back Middle Trapezius Middle Trapezius The Trapezius (trap) muscle is a long, trapezoidshaped 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 ( the shoulder blades down). Based on the SEMG, appears to use the Trapezius mucles significantly more than 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. Mid Trap hard

19 Latissimus Dorsi 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 for arms easy, hard, and. However, based on very limited data, it appears that the Latissimus Dorsi is used when riding a Trikke. Latissimus Dorsi Lat Dorsi hard

20 Erector spinae The Erector spinae muscles run directly down the vertebrae and act to laterally flex and extend the spine. ES hard

21 Buttock Gluteus max 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, and very little activity was noted in this muscle in the or 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. This muscle acts to straighten the leg at the hip when someone is walking or running. When a person is Trikking, there is very little opportunity to flex and extend at the hip during the ride. Glut Max hard Please note that the equipment was not working to read properly on the gluteus muscles, as riding has proven that these muscles are also activated while riding, though in this test the equipment did not pick it up.

22 Gluteus Medius 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. Both and use this muscle relatively similarly and across all types of rides. Glut Med hard

23 Back of the Upper Legs - Hamstrings Biceps Femoris 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 both and. The greatest activation of the Biceps Femoris occurred during the ski jump and. Uphill and were not tested Biceps Fem hard

24 Semitendinous 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 for both and. The greatest activation of this muscle occurred during the ski jump and. Semi Tend hard

25 Front of Upper Legs Quadriceps Rectus Femoris 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. Rectus Femoris Rect Fem hard

26 Vastus Lateralis 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 position or riding. VLO hard

27 Lower Legs Calf Muscles 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 s riding style allows for more activation of the Gastrocnemious muscle than s riding style. uses a plantar flexion motion to move the Trikke, while remains more flat footed doing the ride. Lateral and Medial Gatronemious Lat Gastroc hard Med Gastroc hard