Exercise physiologists have made a career of not only interpreting data, but determining which tests produce the most useful information. VO2 max, FTP, LT, HR, HRV, BL, WPM, WTH? SMASMT. So Many Acronyms So Many Tests.
Here, two exercise physiologists identify the tests they believe produce information that’s most useful for triathletes in planning and maximizing their training.
“Test, don’t guess” is the philosophy behind eNRG Performance, and founder Bob Seebohar’s approach to finding optimal fitness. But he admits, the sheer number of tests out there is overwhelming. He takes the guesswork out of tests by offering his top five choices:
1. Metabolic Efficiency
A 25 to 40-minute, sub-maximal test done on the treadmill or bike (or bike to run for triathletes) that measures how efficient the athlete is at using their stores of fat and carbohydrate. Data shows whether fat or carbohydrate is being used, and at what intensity (power, pace, heart rate) the body starts using more carbohydrate than fat. This information can be used to adjust daily nutrition to extend the athlete’s ability to burn fat at high intensity, and preserve carbohydrates.
2. Lactate Threshold (LT)
A 30 to 50-minute test in which blood samples are taken after each progressively more intense stage. The point at which the body produces more lactate than it can clear is the lactate threshold. This test helps determine training zones, and whether the athlete’s training is appropriate for the goal race.
3. Heart Rate Variability (HRV)
Wrist or chest strap monitors measure the variability in heart beats that helps to indicate if an athlete is recovering from hard workouts/adapting to stressors. HRV may also be affected by sleep, nutrition, and other life stressors, so it’s best taken daily and tracked over weeks or months, to illustrate trends rather than day-to-day variations.
4. Sweat sodium concentration
This is a one-time, non-exercise test that measures the concentration of sodium in sweat, which together with the rate of sweating, can help determine a customized hydration and electrolyte supplementation plan. This is key, especially if you train or race in hot, humid climates.
5. Biomarker/Vitamin D testing
Due to sunscreen use and protective clothing, Vitamin D deficiency in the U.S. is quite high. This is an easy test that should be done at least two to three times per year.
Michael Parker of Parker Performance Training is a proof-is-in-the-pudding kind of guy. “In-season, racing is the best form of testing in triathlon,” he said. With that philosophy, about four times per year (one of them in the racing season) Parker uses shorter bouts to simulate the demands of a race, namely power/pace at Function Threshold Power (FTP). Critically, FTP takes into account the body’s ability to produce and clear lactate while maintaining a fairly high intensity. He uses information from these testing sessions to determine an athlete’s training zones. Another reason he focuses on FTP? “It’s highly trainable,” Parker said. A test of 45 to 60 minutes, like the Hour of Power he has outlined below, is the best indicator of lactate threshold, but a hard effort like that is difficult to prepare for, recover from, and motivate athletes to complete. Parker has found some shorter protocols are as useful, and easier to build into the training schedule.
6. Cycling Gold Standard: Hour of Power
10 min. Easy riding
4 x 1 min. hard, 1 min. rest
5 min. Easy riding
60 min. Time trial
This protocol is very hard and can often be gleaned from post-race data. Performed outside of race conditions, cyclists find it difficult and not fun.
7. Cycling 5/20 FTP Protocol
Warm-up: 10 min. ramp from 55-85% FTP
4 x 1 min. hard, 1 min. rest
5 min. Easy
Main Set #1: 5 min. ALL OUT (evenly paced, typically between 110-120% FTP)
10 min. Easy
Main Set #2: 20 min. Time trial (Evenly paced best effort, very important)
Cooldown: 10 min. Easy
It’s important to include the five minutes at VO2max intensity to burn off some freshness in the legs and reduce anaerobic energy contribution to the 20-minute time trial.
8. Running FTP
Warm-up: 10 min. Easy
Main Set: 30 min. flat (no hills) time trial
Cooldown: 5 min. Easy/walk
Note: Heart rate recorded on a flat course can help mitigate the limitations of pace during windy or hilly conditions.
9. Run a Local 5K or 10K Loop
Every six to eight weeks, run a familiar loop under similar conditions and record your time, heart rate, and RPE. This is a simple method to track training progress at similar distances.
10. T-30 Swim Protocol
Warm-up: 400 easy
Main Set: Swim as far as possible in 30 minutes. This should be evenly paced.
Cooldown: 200 easy
Small changes in technique can result in immediate changes in velocity, but T-30 has been validated as a reliable determinate of aerobic capacity in swimmers.