Muscular fatigue is due to accumulation of

Options

A. Pyruvic acid
B. Glycogen
C. Lactic acid
D. Uric acid

Answer

To answer the question "Muscular fatigue is due to accumulation of," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Muscular Fatigue**:
- Muscular fatigue refers to the decline in ability of a muscle to generate force. It can occur due to various biochemical processes in the muscle cells during intense exercise.

2. **Identifying Energy Sources**:
- Muscles primarily use glucose and glycogen as energy sources. These are broken down through aerobic respiration (in the presence of oxygen) and anaerobic respiration (in the absence of oxygen).

3. **Role of Oxygen**:
- Under normal circumstances, muscles utilize oxygen to produce energy efficiently through the citric acid cycle. This process generates ATP (adenosine triphosphate), which is the energy currency of the cell.

4. **Anaerobic Conditions**:
- During intense exercise, when oxygen supply is insufficient, muscles switch to anaerobic respiration. This process leads to the breakdown of glucose and glycogen without oxygen.

5. **Lactic Acid Production**:
- The byproduct of anaerobic respiration is lactic acid. As exercise continues and oxygen remains low, lactic acid accumulates in the muscle cells.

6. **Effect of Lactic Acid**:
- The accumulation of lactic acid is associated with the sensation of fatigue and muscle soreness. It interferes with muscle contraction and contributes to the feeling of tiredness.

7. **Conclusion**:
- Therefore, muscular fatigue is primarily due to the accumulation of **lactic acid** in the muscles.

### Final Answer:
Muscular fatigue is due to the accumulation of **lactic acid**.

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