About

This tool is designed to simulate the programming logic of a professional fitness coach, generating High-Intensity Interval Training (HIIT) sessions based on available equipment and time constraints. By utilizing principles of metabolic conditioning, the generator structures workouts to maximize EPOC (Excess Post-exercise Oxygen Consumption).

Unlike simple randomizers, the internal algorithm uses muscle-group balancing to prevent local fatigue failure before systemic cardiovascular exhaustion. This ensures that a user can maintain a high intensity, defined by the variable I, throughout the duration t of the session.

The tool supports standard functional fitness formats including AMRAP (As Many Rounds As Possible), EMOM (Every Minute on the Minute), and Tabata protocols. Audio cues and synthetic voice synthesis are generated client-side to guide the athlete through intervals without needing to look at the screen.

Formulas

To determine the target heart rate for a HIIT session, we utilize the Karvonen Formula, which accounts for resting heart rate (HR_rest) to find the Heart Rate Reserve (HRR).

Target HR = (HR_max − HR_rest) × %Intensity + HR_rest

Where maximum heart rate is estimated as:

HR_max ≈ 208 − (0.7 × Age)

Variables:
HR_max = Maximum Heart Rate (bpm)
HR_rest = Resting Heart Rate (bpm)
%Intensity = Desired effort level (0.0 - 1.0)

Reference Data

Intensity Zone	% Max HR (HR_max)	Energy System	Primary Fuel	RPE (1-10)
Recovery / Warmup	50 - 60%	Oxidative	Fat	2 - 3
Aerobic Endurance	60 - 70%	Oxidative	Fat/Glucose	4 - 5
Aerobic Power	70 - 80%	Glycolytic	Glucose	6 - 7
Anaerobic Threshold	80 - 90%	Glycolytic	Glycogen	8 - 9
VO₂ Max / HIIT	90 - 100%	Phosphagen	ATP-CP	10

Frequently Asked Questions

AMRAP stands for "As Many Rounds/Reps As Possible" within a fixed time (e.g., 20 minutes). Your goal is density of work. EMOM stands for "Every Minute On the Minute". You perform a set task at the start of the minute and rest for the remainder. EMOM prioritizes recovery management and consistency.

It is an approximation based on MET (Metabolic Equivalent of Task) values. For HIIT, the MET value usually ranges between 8.0 and 12.0 depending on body weight and true intensity. Actual burn varies by +/- 20% due to individual metabolic efficiency.

This is called "Concurrent Training". Mixing modalities forces the body to adapt to both aerobic and anaerobic demands, improving overall "Work Capacity" - the ability to perform physical work over time.

Yes. This tool is a Progressive Web App (PWA) compatible architecture. All logic, including the voice synthesis and beep sounds, is generated by your browser. No internet connection is required after the page loads.