James de Lacey is a strength and conditioning coach with an MSc in Sport & Exercise Science and more than a decade of experience in professional sport spanning professional and international rugby/rugby league. He now focuses on combat sports to prepare fighters under Sweet Science of Fighting.

Do fighters really need zone 2 cardio? Strength and conditioning coach James de Lacey of Sweet Science of Fighting joins Dr. Mike T Nelson to challenge the "big aerobic base first" playbook for combat sports, from heart rate recovery and short-rest sprint intervals to muscle oxygen (NIRS) data. They also dig into VO2 max, wearables and why AI-written programs often miss the mark.

Expect to learn why James questions the “huge aerobic base” approach for fighters, how heart rate recovery and heart rate kinetics can reveal more than time in zones, how short-rest sprint intervals and a simple air bike baseline test can guide programming, what muscle oxygen (NIRS) data can and can’t tell you, why trends beat single data points from wearables, and why generic AI-written programs often miss the mark—and much more.

Connect with James:

• sweetscienceoffighting.com
• jamesdelacey.com
• Sweet Science of Fighting on Instagram
• Sweet Science of Fighting on YouTube

Episodes you'll enjoy next:

• Episode 326: Row Hard, Breathe Easy: Boosting Aerobic Capacity with Dr. Kenneth Jay: Dr. Kenneth Jay on rowing and boosting aerobic capacity (Mike credits Dr. Jay for the bioenergetic testing he mentions in this conversation).
• Episode 221: Training performance, nitric oxide, blood flow, and more via the NNOXX device with Evan Peikon: Evan Peikon on training performance, nitric oxide and blood flow via the NNOXX device (Mike mentions Evan in this conversation).

Episode Timestamps:

• 03:35 The biggest conditioning mistake in MMA
• 05:50 Why sprints are more aerobic than you think
• 07:46 Do fighters need a huge aerobic base?
• 09:44 VO2 max, muscle limits and oxygen testing
• 11:57 Conditioning trends and training volume
• 15:36 Zone 2, time costs and the 80/20 debate
• 22:10 Heart rate response and recovery between rounds
• 25:43 Mike’s rower test and heart rate recovery
• 28:25 Air bike sprints with short rests
• 31:44 Muscle oxygen and power between repeats
• 34:19 Testing and training each athlete’s limiter
• 41:47 Flexible Meathead Cardio and technical training
• 46:05 Elite athletes, VO2 max and training context
• 50:22 NIRS, oxygen drops and peak power
• 57:18 Why trends beat single test results
• 1:02:56 Wearables, coaching judgment and session design
• 1:06:57 AI programs and generic training blocks
• 1:13:02 Training around life and where to find James

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