"FTP" and 4 mmols of lactate have nothing to do with each other. I would not use 4 mmol to estimate anything really - in this test all it indicates is your current wattage output @ 4 mmol during a 2 min graded exercise test.
Misconceptions about some determination of "lactate threshold" is that it is equivalent to 4 mmol and/or "ventilatory threshold"- it's just simply not the case. 4 mmol and/or ventilatory threshold is certainly not "max 30 minutes sustainable wattage" in all athletes/humans.
Equal work capacity limits at various power or energy outputs is common assumption with use of "lactate threshold", FTP, and even VO2 max testing. The typical application of this data is that everyone's work capacity at various percentages of those data points is the same. Assume nothing- tons of people can't even sustain 10 watts for 30 minutes let alone 30 min @ 4 mmol- this is an individual capacity issue and can be trained but short sighted to assume everyone's capacity is the same at 4 mmol or any other percentage of work output is the same.
I am not exactly sure which protocol they used in your test but most tests will stop at "lactate threshold" or 4 mmol. When using lactate as a metric of looking at an individual's work output or changes in fitness, it is important to measure current physiological range of that athlete.
Today, 4 mmol can be 100% of your physiological range but 6 months ago when you tested 4 mmol could have been 25% of your physiological range. So, depending on this one data point, 4 mmol, as your reference point will simply not give you the answers you are looking for in terms of understanding your current physiology and fitness levels. An individual's physiological range can be very dynamic and needs to be considered when using any lactate data for evaluating performance changes.
I suggest figuring out why are you using these tests, which ones are most relevant to your training/performance objectives, and how is the test influencing your training plan/decisions to improve your performance :)
Physiologist. CEO/Founder Go Athletics. Coach/Consultant to Pros, Olympians, NCAA Champions, HS and Recreational coaches and athletes. 5x TeamUSA member, Ex-Pro Runner, NCAA All-American, now enabling others to achieve their potential.
Misconceptions about some determination of "lactate threshold" is that it is equivalent to 4 mmol and/or "ventilatory threshold"- it's just simply not the case. 4 mmol and/or ventilatory threshold is certainly not "max 30 minutes sustainable wattage" in all athletes/humans.
Equal work capacity limits at various power or energy outputs is common assumption with use of "lactate threshold", FTP, and even VO2 max testing. The typical application of this data is that everyone's work capacity at various percentages of those data points is the same. Assume nothing- tons of people can't even sustain 10 watts for 30 minutes let alone 30 min @ 4 mmol- this is an individual capacity issue and can be trained but short sighted to assume everyone's capacity is the same at 4 mmol or any other percentage of work output is the same.
I am not exactly sure which protocol they used in your test but most tests will stop at "lactate threshold" or 4 mmol. When using lactate as a metric of looking at an individual's work output or changes in fitness, it is important to measure current physiological range of that athlete.
Today, 4 mmol can be 100% of your physiological range but 6 months ago when you tested 4 mmol could have been 25% of your physiological range. So, depending on this one data point, 4 mmol, as your reference point will simply not give you the answers you are looking for in terms of understanding your current physiology and fitness levels. An individual's physiological range can be very dynamic and needs to be considered when using any lactate data for evaluating performance changes.
I suggest figuring out why are you using these tests, which ones are most relevant to your training/performance objectives, and how is the test influencing your training plan/decisions to improve your performance :)
Physiologist. CEO/Founder Go Athletics. Coach/Consultant to Pros, Olympians, NCAA Champions, HS and Recreational coaches and athletes. 5x TeamUSA member, Ex-Pro Runner, NCAA All-American, now enabling others to achieve their potential.