Intense Exercise and the Awakening of Zone 2

The hemodynamics of effort and the body that creates intelligence

(Consciousness in First Person • Decolonial Neuroscience • Brain Bee • O Sentir e Saber Taá)

O Sentir e Saber Taá — when effort becomes a question inside my body

I start to move.
At first, my legs obey easily. Breathing is quiet, rhythm regular.
This is still Zone 1: my body on automatic pilot.

Then the pace increases.

My breathing deepens, my chest opens, my step becomes heavier and more precise at the same time.
There is a point in the run, on the bike, on the rowing machine, where something clicks:

• muscles burn, but not too much,
  
  

• breathing is intense, but still organized,
  
  

• attention narrows and, at the same time, becomes clear,
  
  

• thoughts simplify: just the next movement, the next breath.
  
  

In that moment I feel:

If I push just a little more, I lose myself.
If I stay exactly here, I awaken.

This is how Zone 2 feels from the inside:
effort that does not destroy; tension that opens space instead of closing it.
Taá — the feeling-before-knowing — appears as a question in my own hemodynamics:

How much effort creates intelligence,
and how much effort only burns me out?

It is here that intense exercise and neuroscience meet.
And it is exactly this frontier that one of the 2025 fNIRS studies we comment on —
the NeuroImage article associated with code S1053811925004951,
on prefrontal hemodynamics during high-intensity exercise — tries to model in numbers what my body already knows in silence.

Feeling, evidence and decolonization of effort

When I look honestly at my own history with exercise, I notice how colonized my idea of effort is.
I was taught that:

• the body is a machine to be optimized,
  
  

• tiredness is failure,
  
  

• pain is a proof of moral value,
  
  

• resting is laziness.
  
  

This same logic appears in much of sports science:
the body is reduced to a motor, the brain to a command center, performance to a number.

But when I feel my body before I think — when Taá appears — I realize that there is no separation between Neuroscience, Politics and Spirituality (Utupe, Xapiri, living memory):

• how I train is also how I learn to obey or resist systems,
  
  

• how I breathe under effort says how I deal with pressure and control,
  
  

• how I listen to the limits of my body says how I listen to the limits of the planet.
  
  

Zone 2 is not only a metabolic point.
It is a political and spiritual threshold:
between a body enslaved by productivity and a body that creates intelligence through measured effort.

The study in focus: prefrontal fNIRS and intense exercise

In the 2025 NeuroImage study (code S1053811925004951), the authors use
functional near-infrared spectroscopy (fNIRS) to investigate what happens in the prefrontal cortex when we cross from:

• light effort → moderate effort → very intense effort.
  
  

The central questions are:

1. How does prefrontal oxygenation (O₂–Hb and HHb) change with increasing physical load?
   
   

2. Is there an intensity range where the prefrontal cortex works better — a physiological Zone 2?
   
   

3. What happens to cerebral hemodynamics when effort becomes excessive?
   
   

Methods — how the brain’s “light” is measured during effort

Participants perform graded exercise (for example, cycling or treadmill) with increasing intensity, while fNIRS optodes are placed over the dorsolateral and medial prefrontal cortex.

The analysis includes:

• GLM (General Linear Model)
  
  

• models the expected hemodynamic response function (HRF) for each effort condition;
  
  

• estimates how much each level of effort changes O₂–Hb and HHb in the cortex.
  
  

• Short-channels
  
  

• measure superficial blood flow in scalp and skin;
  
  

• are used as regressors to remove systemic noise (heart, skin vasculature), isolating cortical signal.
  
  

• ICA and PCA
  
  

• ICA (Independent Component Analysis) separates components clearly linked to motion, systemic physiology or instrument noise;
  
  

• PCA (Principal Component Analysis) reduces dimensionality, highlighting the main patterns of change across intensities.
  
  

• Physiological measures
  
  

• heart rate, oxygen consumption, ventilation, perceived exertion;
  
  

• sometimes lactate or SpO₂ to anchor the physiological meaning of each intensity.
  
  

This is the basic pipeline:
GLM + HRF + short-channels + ICA/PCA —
a modern standard for fNIRS in exercise neuroscience.

Main findings: a prefrontal “sweet spot”

Across similar studies, a robust pattern appears, and this NeuroImage work reinforces it:

• at low intensities:
  
  

• small changes in prefrontal O₂–Hb;
  
  

• the system is comfortable, almost bored.
  
  

• at moderate intensities (our Zone 2 window):
  
  

• significant increase in O₂–Hb and total hemoglobin (tHb) in prefrontal regions;
  
  

• the brain receives more blood and oxygen exactly when effort becomes demanding but still sustainable;
  
  

• cognitive control and decision-making tend to be preserved or even improved.
  
  

• at very high intensities:
  
  

• O₂–Hb may plateau or even decrease,
  
  

• HHb can increase locally, signaling a relative oxygenation drop;
  
  

• performance in cognitive tasks (if present) deteriorates;
  
  

• the system enters a survival mode: keep moving, but think less.
  
  

Translated into Taá:

there is an effort level at which my brain shines,
and another where my brain simply tries not to drown.

Reading the data through our concepts

Mente Damasiana

The prefrontal cortex is part of the territory where interoception and proprioception meet and create the Damasian Mind: the feeling of “me, here, now.”

In Zone 2:

• the heart accelerates,
  
  

• respiration deepens,
  
  

• muscles send intense feedback,
  
  

and the prefrontal cortex integrates everything into a state of lucid effort.
The fNIRS curve is the hemodynamic face of this lived experience.

Eus Tensionais

Each effort level is a different Eu Tensonal:

• the “lazy self” of low intensity,
  
  

• the “creative self” of Zone 2,
  
  

• the “survival self” of over-exertion.
  
  

The NeuroImage data show that these selves are not metaphors:
they correspond to different patterns of prefrontal oxygenation.

Zones 1 / 2 / 3

• Zone 1: low demand, little modulation in O₂–Hb;
  
  

• Zone 2: flexible, high, stable hemodynamics — the body creating intelligence;
  
  

• Zone 3: overdrive; the system is so tense that creativity collapses and only command–obedience loops remain.
  
  

In politics and spirituality, Zone 3 is the space of ideology, fear and blind obedience.
In exercise, it is the place of overtraining and self-punishment.
In both cases, the signal is the same: loss of fruição, loss of open presence.

DANA and metabolic wisdom

The DNA (DANA, as we name its intelligence) programmed a system where:

• moderate, sustainable effort
  
  

• improves vascular function,
  
  

• strengthens networks,
  
  

• stabilizes mood and cognition.
  
  

Zone 2 is not a fitness fashion.
It is a design principle of the body.

Yãy hã mĩy (origem Maxakali)

The Maxakali concept of Yãy hã mĩy — imitating to become — appears here as:

• imitating breathing of those who regulate effort wisely,
  
  

• imitating rhythms that create resilience, not burnout.
  
  

The athlete who learns to stay in Zone 2 is practicing a Yãy hã mĩy of effort:
imitating the body that knows how to grow without breaking.

Where science adjusts our ideas

This study and others like it correct simplistic views such as:

• “The more intense, the better.”
  
  

• “If I am not on the edge of collapse, I am not evolving.”
  
  

Evidence shows:

• too little effort does not awaken intelligence;
  
  

• too much effort shuts down prefrontal regulation;
  
  

• intelligence is created in the middle zone of sustainable tension.
  
  

For Latin America, this is also a metaphor:

We do not need heroic suffering to evolve as peoples.
We need well-regulated effort — metabolic, political, spiritual.

Normative implications for LATAM

• Education:
  build schedules, breaks and physical activities that respect Zone 2 — neither apathy nor toxic pressure.
  
  

• Public health:
  exercise prescriptions should speak of hemodynamics and attention, not just calories and aesthetics.
  
  

• Work and city design:
  create flows that avoid constant Zone 3 (chronic stress) —
  transport, noise, time pressure, digital overload.
  
  

• Climate and consumption:
  the same logic that says “train until you fall” says “produce until the planet collapses.”
  Learning Zone 2 in the body is also learning planetary Zone 2.
  
  

Keywords for scientific search

“NeuroImage 2025 S1053811925004951 fNIRS high-intensity exercise prefrontal cortex cerebral oxygenation hemodynamics Zone 2 training metabolic threshold O2-Hb HHb GLM short-channels ICA PCA”