Boxing
Rounds, not rage.
Round 1 is alactic. Round 4 is glycolytic. Round 8 is aerobic. Training boxing like it’s one workout wastes all three. FitX schedules each system separately so you peak on the weekend you fight — not two weeks before, not the morning after.
What FitX brings to the gym.
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Round-structured conditioning
Heavy-bag intervals at alactic–glycolytic intensity, roadwork at aerobic base, mitt work at specific-fatigue — FitX separates the three.
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Heart-rate zones across rounds
Log HR by round, FitX maps it onto Chaabene’s boxing zone model — you see whether round 5 broke you aerobically or glycolytically.
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Sparring-load periodization
Hard spar is a 90-RPE session. Tracking it the same as bag work is how fighters overtrain. FitX weights sparring at its true cost.
Why the round matters.
Smith and Chaabene independently mapped the energy-system contribution of a three-minute boxing round at ~30 % alactic / 50 % glycolytic / 20 % aerobic. Over a twelve-round bout, that inverts — the last rounds are dominantly aerobic. Periodization that trains all three on separate days is what produces fighters who don’t fall apart in round 9.
Read the full methodologyEight-round sparring session — HR drifts up despite drop in output, a classic aerobic-system signature.
Ready to train the rounds, not the bag?
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