Laboratory 4
LACTATE THRESHOLD LABORATORY
(Assessment Lab)
Introduction
The objective of this lab is to measure and observe methods of determining Lactate threshold using invasive techniques.
PROGRESSIVE MAXIMAL TREADMILL TEST:
This is a progressive maximal test used to determine aerobic power and lactate threshold following the protocol from SSNZ – Athletics; Middle and Long Distance Running, Craig Palmer, 2003.
Procedure 1:
STUDENT RESPONSIBILITIES
1 4 students to act as subjects (male & female)
2 Responsible for heart rate monitoring (Sunto gear)
3 Controlling treadmill with remote software
4 Lactate testers x 2 (double measurements required)
5 Connecting the subject to the cart and subject safety
6 Timer and co-ordination
7 Everyone: support and encouragement
• The subjects will need to warm-up before starting the test set-out in Table 4.1.
• Elevation remains CONSTANT at a gradient of 1.5%.
Table4.1:Running speeds (km/hr)
Stage Time Female Male
1 0 – 3 minutes 8 – 10 km/h 10 – 12 km/h
3 – 4 REST REST
2 4 – 7 10 – 12 12 – 14
7 – 8 REST REST
3 8 – 11 12 – 14 14 – 16
11 – 12 REST REST
4* 12 – 15 14 – 16 16 – 18
15 – 16 REST REST
5 16 – 19 15 – 17 17 – 19
19 – 20 REST REST
Increase each 3 minute stage by 1 km/h Increase each 3 minute stage by 1 km/h
• * Increase speed by 2 km’s/h per stage for the first 4 stages or until the first 1 mmol/L increase in blood lactate, from then on increase by 1 km/hr
• Before the END of each 3 minute stage & 1 minute rest periods record the heart rate
• During the 1 minute rest period measure the Lactate levels (x2)
• Encourage the subject to continue till they are completely maxed out. The subject should continue and start the next 3 minute stage even though they may feel they may not be able to complete the stage.
• Make sure the subject warms down, regularly checking on how they are feeling
Table4.2: Treadmill Lactate threshold test results
Stage Running Speed (km/h) Heart Rate Lactate
1
2
3
4
5
6
7
PROGRESSIVE MAXIMAL CYCLE TEST:
This is a progressive maximal test used to determine aerobic power and lactate threshold following a converted protocol from SSNZ – Cycling New Zealand; Carl Paton.
Procedure 2:
STUDENT RESPONSIBILITIES
1 Two students to act as subjects (Male & Female) 2 Responsible for heart rate monitoring
3 Controlling Watt bike
4 Timer and co-ordination
5. Measuring Lactate (x2)
6 Everyone: support and encouragement
• The subject will need to warm-up before starting, at or below the starting level of the incremental test (see Table 4.3).
• TheWatt bike test to be used a continuousstepincremental test. The step duration is four (4) minutes and the step increment is 40 watts. Approximate starting workloads are listed in Table 4.3 (some individual adjustment maybe required).
Table 4.3:Watt bike Lactate increment test approximate starting workloads
Group Start load and increment
Novice 100W with 40W increase
Female 100W with 40W increase
Junior Male 140W with 40W increase
Senior Male 180W with 40W increase
• Heart rate and lactate readings are to be taken during the last 30 seconds of each stage, without the subject stopping
• Power up the Watt bike and select just ride. Ensure the magnetic resistance is turned off. Use the (air) resistance lever to adjust the resistance. Refer to table 4.5 for Watt bike resistance adjustments
• Encourage the subject to continue till they are completely maxed out. The test is completed when the subject cannot keep the rpm’s above 60.
Make sure the subject warms down, regularly checking on how they are feeling
• Record the results in Table 4.4 below.
•
Table 4.4: Cycle lactate threshold test results
Stage Watts Heart Rate Lactate
1
2
3
4
5
6
7
Draw the following graphs and label the threshold points for each graph
Graph 1: Lactate & Heart Rate over Time for Treadmill Test
Graph 2: Lactate & Heart Rate over Time for Cycle Test
Questions(These questions needs to be incorporated into the discussion part of your lab report)
• What is MLSS?
• What is OBLA?
• What is the common reference point for determining OBLA?
• What (at what point) is the (theoretical) lactate threshold for the treadmill and cycle tests regarding?
percentage of VO2 max
in terms of a heart rate value
in terms of running speed (treadmill), cadence/watts (cycle)
How does this compare to your findings?
• Why are these values important?
Table 4.5 Power Table for Wattbike Pro
Power Table for Wattbike Pro
Cadence
(rpm) Level 1 Level 2 Level 3 Level 4 Level 5 Level 6 Level 7 Level 8 Level 9 Level 10
40 25 30 30 40 45 45 50 50 55 55
45 35 40 40 45 50 55 55 60 60 65
50 40 40 50 55 60 65 70 70 75 80
55 50 50 60 70 75 80 90 95 100 105
60 60 60 70 80 90 100 110 115 120 125
65 70 80 90 100 115 125 135 150 155 160
70 85 90 105 120 135 150 165 175 185 190
75 100 105 130 150 175 185 200 210 225 240
80 115 125 150 170 195 215 235 250 270 280
85 130 145 170 195 225 260 275 295 320 340
90 150 165 200 235 265 300 325 350 375 390
95 175 185 225 265 310 350 375 400 425 450
100 195 215 260 310 355 395 430 465 500 520
105 210 230 295 350 400 445 490 525 565 600
110 245 270 330 395 455 510 555 600 645 675
115 270 310 380 445 515 575 625 675 725 760
120 300 335 410 490 570 640 695 750 810 850
125 330 370 450 545 635 710 775 835 900 945
130 360 405 495 600 705 785 855 925 995 1045
The watts produced at a given Level and Cadence are a guide only - there will be some variation between these valves and each Wattbike