Set your intervals. Follow the rhythm.
The HIIT Timer lets you configure up to 10 exercises with work time, rest, cycles, colors and sound cues, so you can keep the rhythm without losing control of the session.
Customisable Timer
Up to 10 exercises: work, name & colour, rest, cycles. A gong marks the start of each work interval. Beeps mark the final 3 seconds of work.
What does HIIT mean?
HIIT stands for High-Intensity Interval Training.
The principle is simple: alternate short periods of intense effort with recovery periods. Work and rest intervals can be adjusted to suit your session. The aim is to produce a controlled, intense effort within a limited time frame.
Why is this format so popular?
Time efficiency
A short session can generate a strong cardio-metabolic stimulus when the intensity is genuinely present.
Cardio & metabolism
HIIT can improve cardiorespiratory capacity and increase the energy expenditure linked to the effort.
Motivation
The format is rhythmic, readable and challenging. Colors, sounds and cycles reinforce engagement during the session.
Measurable progression
Durations, rest periods, exercises and cycles can be adjusted progressively without improvising every session.
How to build a HIIT session
Work duration
Start often between 20 and 40 seconds. Move toward 60 seconds only if movement quality remains stable.
Rest duration
Rest can represent 50 to 150% of the work time depending on level, objective and exercise selection.
Number of rounds
For most trainees, 6 to 12 rounds are enough. More is not always better if intensity drops.
Exercise selection
Choose movements the client can control: sprints, squats, rowing, cycling, adapted burpees, kettlebell swings or bodyweight exercises.
Recommended progression: improve technique first, then duration, then intensity.
HIIT, aerobic and anaerobic systems
HIIT relies on the alternation between several energy systems. Understanding this logic helps you calibrate interval duration and intensity level more precisely.
Anaerobic alactic
Very short and explosive efforts, generally under 15 seconds.
Anaerobic lactic
Intense efforts of roughly 15 to 90 seconds, with high local fatigue accumulation.
Aerobic
Longer efforts or recovery between intervals, with a substantial contribution from aerobic metabolism.
👉 The right interval depends on the goal: fat loss, performance, endurance or general conditioning.
⚠️ A word of caution for beginners
HIIT is effective, but it becomes problematic when intensity exceeds the trainee’s technical capacity. For a beginner, it is safer to build a foundation of moderate cardio, mobility and strength training before integrating very intense formats.
Injury risk
High intensity increases stress on joints, tendons and tissues.
Technique breakdown
Fatigue can create compensations. Movement must remain clean, even under pressure.
Overtraining
Too much HIIT, too soon, can slow progression and increase nervous system fatigue.
Go further with DietHelper
DietHelper goes further than a simple timer. The goal is to help coaches structure more precise follow-ups: workload, heart-rate zones, circadian rhythm, nutrition and client-profile adaptation.
Tabata
A timer based on the original Tabata protocol to create highly structured sessions.
PLC Calculator
A tool to calibrate workload from a real set and clean repetitions.
CircaTest
A tool to account for circadian rhythm when organizing client follow-up.
EnergyScope
A calculator to define heart-rate zones adapted to the client profile.
Nutrition Planner
A nutrition planner designed to structure precise and usable dietary follow-ups.
Coach follow-up
Complementary tools to reduce improvisation and professionalize decision-making.