The document discusses the three main energy pathways the body uses to produce ATP: anaerobic alactic, anaerobic lactic, and aerobic. The anaerobic pathways produce energy very quickly without using oxygen but can only be used for short bursts of intense activity. The aerobic pathway uses oxygen to break down carbohydrates and fats into ATP, producing more energy over a longer period of time. The type of pathway used depends on the intensity and duration of the physical activity.

1. PHUSICAL EDUCATION DEPARTMENT
I.E.S. PEÑALBA

2. The Human Body needs energy, not only to
move, for vital activities too (to breath, digestion
process, etc)
We get this energy from food and nutrients,
specially from energetic nutrients like carbohydrates
and fats.
To be used by muscle fibers, nutrients must be
transformed into ATP molecules (adenosine
triphosphate). ATP is stored in muscles fibers.
When we break an ATP molecule it breaks free the
energy needed to contract a muscle.

3. ATP MOLECULE

4. There are three main energy pathways the body
uses to get ATP and get energy:
ANAEROBIC PATHWAY (NO O2)
Anaerobic Alactic
Anaerobic Lactic
AEROBIC PATHWAY (with O2)

5. ANAEROBIC PATHWAYS
They are used in short duration and very high intensity activities. On
these pathways O2 does not take part because we need energy very soon.
- ANAEROBIC ALACTIC PATHWAY:
- Activities:
- Duration: very short (from 0 to 15 seconds)
- Intensity: maximum (90-100%)
It uses ATP storaged in muscle cells.
ATP breaksdown generating ADP+P+ENERGY

6. - ANAEROBIC LACTIC PATHWAY (ANAEROBIC
GLYCOLISIS) :
- Activities:
- Duration: from 15 seconds to 2 minutes.
- Intensity: high (80-90%)
- CARBOHYDRATES breakdown into GLUCOSE molecules.
GLUCOSE is storaged in muscles. Without O2, 1 GLUCOSE molecule
breaks down creating 2ATP molecules + LACTIC ACID. Lactic Acid
generates fatigue so when Lactic Acid concentration in muscle is very
high , muscle gives up working because of tiredness (about 2
minutes).

7. AEROBIC PATHWAY
- Activities:
- Duration: more than 2 minutes
- Intensity: medium-low (40-70%)
- This pathway uses oxygen to convert carbohydrates and fats into ATP.
- This process occurs in the mitochondria of the cell.
- Through this process we obtain higher levels of energy (38 ATP), it
does not produce Lactic Acid and fatigue neither, but this process is
slower than the other pathways .
- At the beginning we burn carbohydrates and when we have burnt all
of them we start to use fats (20-30 min)

9. To sum up, now we know that the way our body obtain energy
to do physical activity depends on the intensity and duration of the
activity.
These three energy pathways don´t work alone. We use each
one in a progressive way and depending on the intensity and duration
of the activity and as time progresses each patway become more
important.

10. MIND MAP
ENERGY
SYSTEM
DURATION INTENSITY ENERGY
SOURCE
RESULT
ANAEROBI
C ALACTIC
(NO O2)
0-15 seconds Very high
90-100%
ATP in
muscle cells
1 ATP
ANAEROBI
C LACTIC
(NO O2)
15 seconds to
3 minutes
High
70-90%
Glucose
molecules in
muscle,
2 ATP
+
LACTIC
ACID
AEROBIC More than 3
minutes
Medium-Low
40-70%
Glucose
molecules in
muscle,
blood and
liver
and Fats (20-
30 minutes)
38 ATP