THR-020Z4ThresholdThresholdRunning

Critical Velocity Intervals (Tinman)

5-6 repetitions of 1,000m at critical velocity pace (roughly 30-minute race pace) with 60-90 seconds jog recovery. Specifically develops Type IIa muscle fibers.

Duration: 1h05
Level: Intermediate
Target: Lactate Threshold

Track requiredFlat preferred

Session structure

1h05 · 3 phases

0 min · start1h05 · end

Intensity scaleZ1RecoveryZ2EnduranceZ4Threshold

Warm-up

20min

Z1-Z2Recovery → EnduranceProgressive jog

15min

No zoneDrills and 3× progressive accelerations

5min

Main Set

6 × 1000m/1'

35min

6 ×

Z4Threshold1,000m at CV pace (~30min race pace), 60-90s jog recovery

1000 m

Z1Recovery60-90s light jog

1min

Cool-down

10min

Z1RecoveryRecovery jog

10min

Zone Distribution

Z1Recovery22min30

Z2Endurance7min30

Z4Threshold30min

Total 1h05 · No zone 5min

Tips

CV pace sits between threshold and VO2max, approximately your 30-minute race pace
Short recovery (60-90s) is deliberately insufficient to accumulate D' depletion
All repetitions should be at the same pace, no pace progression
If you don't know your CV, use your 8-10K pace as an approximation

Common Mistakes

Running repetitions at VO2max pace instead of the more moderate CV pace
Extending recovery beyond 90 seconds
Accelerating on the last repetitions instead of maintaining a constant pace

Nutrition & Recovery

Nutrition

Eat your last meal at least 3 hours before the session for optimal digestion.
Carb snack 1 to 1.5 hours before: banana, energy bar, or applesauce.
Avoid high-fiber and high-fat foods before the session (legumes, fried foods).

Hydration

Drink 400 to 500 ml of water in the 2 hours before the session.
Top up with 200 ml in the 15 to 30 minutes before heading out.
Avoid diuretic beverages (excessive coffee, alcohol) in the hours before.

Why it works

Why this format

The lactate threshold (VT2, second ventilatory threshold, ~4 mmol/L) represents the metabolic tipping point beyond which blood lactate accumulation becomes exponential. Training this threshold shifts upward the intensity at which a runner can maintain a lactate steady state, which is the primary determinant of performance from 10K to half-marathon.

Zones solicited

Threshold

Z4 corresponds to lactate threshold intensity. Tempo efforts of 20-40 minutes at this intensity trigger threshold-specific metabolic adaptations: MCT4 upregulation and improved buffering capacity.

Expected adaptations

Increased MCT4 transporter expression (lactate export from muscle fibers)
Improved muscle buffering capacity (carnosine, bicarbonate)
Elevation of lactate threshold as percentage of VO2max (from ~75% to ~85% in elites)
Increased lactate dehydrogenase activity in its oxidative form
Improved psychological tolerance to sustained threshold effort

2 studies

Faude O, Kindermann W, Meyer T (2009) View study →Lactate threshold concepts: how valid are they?
Mader A, Liesen H, Heck H, Philippi H, Rost R, Schürch P, Hollmann W (1976) Zur Beurteilung der sportartspezifischen Ausdauerleistungsfähigkeit im Labor

Continue exploring

Threshold 10K Pace

Z41h07THR-010

Critical Velocity Test

Z51h08ASS-002

Articles

Understanding the 6 Training Zones

10 min

Periodization in Running

8 min

Understanding Supercompensation

6 min

Glossary

CV FTP Lactate Threshold Lactate Threshold Over-Unders

THR-020Z4ThresholdThresholdRunning

Critical Velocity Intervals (Tinman)

5-6 repetitions of 1,000m at critical velocity pace (roughly 30-minute race pace) with 60-90 seconds jog recovery. Specifically develops Type IIa muscle fibers.

Duration: 1h05
Level: Intermediate
Target: Lactate Threshold

Track requiredFlat preferred

Session structure

1h05 · 3 phases

0 min · start1h05 · end

Intensity scaleZ1RecoveryZ2EnduranceZ4Threshold

Warm-up

20min

Z1-Z2Recovery → EnduranceProgressive jog

15min

No zoneDrills and 3× progressive accelerations

5min

Main Set

6 × 1000m/1'

35min

6 ×

Z4Threshold1,000m at CV pace (~30min race pace), 60-90s jog recovery

1000 m

Z1Recovery60-90s light jog

1min

Cool-down

10min

Z1RecoveryRecovery jog

10min

Zone Distribution

Z1Recovery22min30

Z2Endurance7min30

Z4Threshold30min

Total 1h05 · No zone 5min

Tips

CV pace sits between threshold and VO2max, approximately your 30-minute race pace
Short recovery (60-90s) is deliberately insufficient to accumulate D' depletion
All repetitions should be at the same pace, no pace progression
If you don't know your CV, use your 8-10K pace as an approximation

Common Mistakes

Running repetitions at VO2max pace instead of the more moderate CV pace
Extending recovery beyond 90 seconds
Accelerating on the last repetitions instead of maintaining a constant pace

Nutrition & Recovery

Nutrition

Eat your last meal at least 3 hours before the session for optimal digestion.
Carb snack 1 to 1.5 hours before: banana, energy bar, or applesauce.
Avoid high-fiber and high-fat foods before the session (legumes, fried foods).

Hydration

Drink 400 to 500 ml of water in the 2 hours before the session.
Top up with 200 ml in the 15 to 30 minutes before heading out.
Avoid diuretic beverages (excessive coffee, alcohol) in the hours before.

Why it works

Why this format

Zones solicited

Threshold

Z4 corresponds to lactate threshold intensity. Tempo efforts of 20-40 minutes at this intensity trigger threshold-specific metabolic adaptations: MCT4 upregulation and improved buffering capacity.

Expected adaptations

Increased MCT4 transporter expression (lactate export from muscle fibers)
Improved muscle buffering capacity (carnosine, bicarbonate)
Elevation of lactate threshold as percentage of VO2max (from ~75% to ~85% in elites)
Increased lactate dehydrogenase activity in its oxidative form
Improved psychological tolerance to sustained threshold effort

2 studies

Faude O, Kindermann W, Meyer T (2009) View study →Lactate threshold concepts: how valid are they?
Mader A, Liesen H, Heck H, Philippi H, Rost R, Schürch P, Hollmann W (1976) Zur Beurteilung der sportartspezifischen Ausdauerleistungsfähigkeit im Labor