Lab 1_Linear Kinematics _sprint analysis

Lab 1: Sprint Analysis The purpose of this lab is to (1) gain practice computing linear kinematics of walking and running, and (2) observe how humans manipulate stride length, and stride rate to increase speed of locomotion. APPLICATIONS: Kinematic features of running have been examined by biomechanists for such purposes as improving performance and investigating injury mechanisms. Since running is an important fundamental movement, it will be used in this lab to study linear kinematics. In this lab, linear motion will be assumed during running although angular motion is also accruing. PART 1: Critique Sprint Performance EQUIPMENT 40 m running course (cones), 1 tape measure, stop watch, and computer and calculators (used after data collection) PROCEDURES A person will sprint 40 meters while having his/her run timed. Timers will be located at each 5 m of the marked 40 m course. The timers will give time when the runner crossed that zone. Strides in each zone will also be counted during the run. It is easiest to count steps (round to the nearest 0.5 step) and divide by 2. Use the excel document provided to input the accumulative time and the strides per zone. Then, use the time and stride data to calculate/fill in all other columns on the document. Once the data table is complete, build two graphs (description below) in excel. After your graphs are build, copy each graph and past them in this word document. Next, answer the discussion questions. It is easiest to answer the questions on the document. After the questions have been answered, upload this document with your graphs and excel data copied into this document on Canvas. Step #1: Graphs Based on the information from your excel table, construct two graphs to describe your results. Each graph should be properly labeled (axes labels with proper units) with a descriptive title. Be sure to include a legend identifying each line of the graph. Copy and paste your graphs from the excel sheet into this document. Graph #1 - Kinematics Analysis Graph : Display zone time on Y1, zone velocity and zone acceleration on Y2. Plot accumulative time on the horizontal axis (X). Graph #2 - Stride Analysis Graph : Plot Stride Rate for each zone on Y1 and Stride Length for each zone on Y2. Plot accumulative displacement on the horizontal axis (X).

Step #2: Discussion Questions – answer the following questions below. 1. Review the kinematics analysis graph (Graph #1) by reviewing each line. For each variable in the graph (zone time, zone velocity, and zone acceleration), identify when each variables has the highest values. Do the highest values occur more in the first half or second half of the sprint? Next, identify why each variable is highest in these areas of the run. 2. Review the kinematics analysis graph (Graph #1) by reviewing each line. First, describe the relationship between zone time and zone velocity (what happens to one variable when another variable changes?). Next, describe the relationship between zone velocity and zone acceleration (what happens to one variable when another variable changes?). Lastly, describe the relationship between zone time and zone acceleration (what happens to one variable when another variable changes?). 3. With regards to the stride analysis graph (Graph #2), how did stride rate and stride length vary with respect to accumulative displacement? When did the fastest stride rate and longest stride length occur throughout the run? 4. Describe the relationship between stride length and stride rate (what happens to one variable when the other variable changes?). 5. What are possible sources of experimental error that may be present? How would you change this lab activity to be more accurate? 6. Based on the graphs, identify a few times in the sprint where you would advise the runner to concentrate on during training to improve sprint performance. Explain why you chose these times in the run. Replace the table below with a copy of the excel table. Do not upload the excel file on Canvas. TABLE 1. SPRINT ANALYSIS LAB (15) Date Your Name Subject's Name Strides Accel Vel Time Accum Accum Accum Zone Vel Lgth Rate No. per per per Vel Time Displ Disp # per per per per 5 m 5 m 5 m Zone Zone Zone Zone Zone Zone Zone (SV) (SL) (SR) (S) (m/s/S) (m/S) (S/s) (m/s/s) (m/s) (s) (m/s) (s) (m) (m) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Str 5.00 5.00 1 10.00 5.00 2 15.00 5.00 3 20.00 5.00 4 25.00 5.00 5 30.00 5.00 6 35.00 5.00 7 40.00 5.00 8 45.00 5.00 9 50.00 5.00 10 AVERAGE 16

Data collection sheet Walk Fast walk Jog # of strides _12_ # of strides _10.5_ # of strides _9_ Total time _12.6_ Total Time _10.71_ Total time _6.62_ Fast Jog Sprint # of strides _8_ # of strides _7.5_ Total time _6.75_ Total time _4.34_ Data collection table 1. Calculate the magnitude of average velocity (using equations 1 and 2 in the appropriate columns), stride length, and stride rate for each trial. 2. In the last column, convert average velocity (calculated with equation 2) to miles per hour (mph); 1mph = .45m/s. Conditions Displ. # Strides Time Vel. (1) SL SR Vel . (2) Vel . (2) m sec m/s m/strides strides/sec m/s mph Walk 20 m 12 12.6 1.587302 1.666667 0.952381 1.587302 3.550693 Fast Walk 20 m 10.5 10.71 1.867414 1.904762 0.980392 1.867414 4.177285 Jog 20 m 9 6.62 3.021148 2.222222 1.359517 3.021148 6.758116 Fast Jog 20 m 8 6.75 2.962963 2.5 1.185185 2.962963 6.627959 Sprint 20 m 7.5 4.34 4.608295 2.666667 1.728111 4.608295 10.30846 Step #1 - Graphs Input the data collection table into excel. Based on the information from your excel table, construct one graph to describe your results. The graph should be properly labeled (axes labels

with proper units) with a descriptive title. Be sure to include a legend identifying each line of the graph. Copy and paste your graphs from the excel sheet into this document. Graph #1 – Running Profile : Display stride length on Y1 and stride rate on Y2 for each ambulatory condition (i.e., ambulatory condition will be the x-axis labels). Walk Fast Walk Jog Fast Jog Sprint 0 0.5 1 1.5 2 2.5 3 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Running Profile Stride Length Stride Rate Ambularoy Conditions Length (m/Strides) Rate (Strides/sec) Step #2 - Discussion Questions: Answer the questions below. 1. Based on the data from this lab, how did stride length and stride rate change as velocity increased? 2. Consider the stride length and stride rate of an elite sprinter running near 10m/s. Based on the graph below and your data, compare the stride lengths and stride rates of an elite sprinter to your own stride lengths and stride rates. What changes could be made to improve your performance so it is more like an elite sprinter? Would you change your stride rate, stride length, or both?