3x Olympian Hazel Clark and Exercise Physiologist Shannon Grady to bring a new series to MileSplit. Tuesday Topics are set to tackle specific issues and training tips for the high school athlete. Tune in every Tuesday to dig into the sport science of Track & Field.
Episode 6: Pre-Season/Indoor 800m Training Phase I Featuring Special Guest J.J. Clark
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It's time to REVOLUTIONIZE your performance!
This comprehensive pre-season training plan presents a science-based and data-driven approach to ensure a well-balanced physiology for successful 800m racing.
For over two decades, the world's top middle distance runners and coaches have had access to these advanced sport science insights and lactate based training applications that have produced a multitude of NCAA, Olympic and World Champions. This data-driven training approach will deliver an unparalleled value to high school athletes and coaches to optimize peak performance in the 800m event.
This 2-4 Week AF phase is aimed to build a minimum aerobic base for endurance while priming upper aerobic power with economy intervals. This AF phase provides high school 800m runners a minimum aerobic foundation preparation period to prepare the body for more volume and intensity in subsequent training phases while reducing risk of injuries. The pre-season or indoor season AF phase length can be determined based on athlete readiness and if the athlete is racing an indoor season.
Main System: AF
Priming System: ARC-2 and ARC-1
Phase I System Descriptions
Aerobic Foundation (AF)- Develop foundation of the aerobic system by increasing fat metabolism, increase the number of aerobic enzymes, increase size and number of mitochondria, increase capillarization, and improve lactate clearing rate in order to adequately and optimally develop all the other systems. Train lactate power and capacity between 0.7 and 3 mmol/L.
Neuromuscular Adaptation Glycogen Sparing (NAGS)- Increase neuromuscular economy, efficiency, speed, muscular/tendon elasticity, strength and enhance lactate systems without glycogen depleting effects.
Recovery And Maintenance (R&M)- Promote recovery, gluconeogenesis, and lactic acid removal following glycogen-depleting training such as; high intensity intervals or workouts longer than 60 continuous minutes. Maintenance of cardiovascular and skeletal muscle adaptations. Lactate less than 3.0 mmol/L.
Phase I Workout Descriptions
AF- Steady state runs ideally using Zone 2 heart rate. Runs should be at least 5 minutes continuous with less than 60 seconds rest. Build up to longer continuous efforts at Zone 2 heart rate. An AF effort should be achieved with a low breathing rate and easy to hold a conversation.
NAGS: Economy Intervals at ARC-2 and ARC-1 pace, 15-60 second intervals with 1 to 2 work to rest ratio.
R&M: Steady state runs or cross training sessions ideally using Zone 1 to 2 low heart rate. Runs or cross train efforts should be at least 5 minutes continuous with less than 60 seconds rest. Maximum length of a recovery session should be no more than 45 minutes. R&M efforts should be achieved with a low breathing rate and easy to hold a conversation.
Sample Phase I Training Week
AF with ARC-2 & ARC-1 Priming
Check out Coach Hazel Clark's 2026 Summer Running Camps https://www.ussportscamps.com/coaches/hazel-clark and 12-Week Customized High School 800m training plan, available on the MyBya mobile app. Go to www.mybya.com for discount codes.