======Muscle Fatigue======


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**Materials: **{{$demo.materials_description}}\\
**Difficulty: **{{$demo.difficulty_description}}\\
**Safety: **{{$demo.safety_description}}\\
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**Categories:** {{$demo.categories}}
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**Alternative titles:** Finger Marathon
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====Summary====                   
{{$demo.summary}}



====Procedure====  
  - Gather materials per pair: 1 spring clothes peg (same type for all pairs), stopwatch or timer, data sheet, pencil, and optional alcohol wipes for shared pegs.
  - Standardize the setup: use the same peg model and spring strength for all students; hold the peg between thumb and forefinger of the writing hand unless testing hand differences.
  - Practice for 5–10 s to learn the full open–close motion. The peg must open fully each count; partial opens do not count.
  - Assign roles: Performer (squeezes and counts aloud) and Timekeeper (calls time marks and records counts). You will swap roles after the first run.
  - Run 1 (writing hand): on “go,” perform as many full opens as possible in 30 s. Timekeeper records the total for 0–30 s.
  - Rest exactly 15–30 s (use the same rest for everyone).
  - Continue immediately for the next two intervals without resetting the count aloud. Timekeeper records the additional opens achieved during 30–60 s, then during 60–90 s (counts per interval, not cumulative).
  - Swap roles and repeat Run 1 with the partner following the same timing and rest.
  - Optional Run 2 (non-writing hand): repeat the three 30 s intervals to compare hands.
  - Graph results for each person: x-axis = interval (0–30 s, 30–60 s, 60–90 s); y-axis = opens per 30 s interval. Plot both partners on the same axes for comparison.
  - Analyze briefly: note where performance drops, describe sensations (burning, slowing), and connect to energy use (aerobic early, increasing anaerobic contribution later). Record one or two sentences interpreting the pattern.




====Links==== 
📄 ACTIVITY: Finger marathon - Science Learning Hub: [[https://www.sciencelearn.org.nz/resources/1926-finger-marathon]]\\


====Variations====
  * Recovery test: repeat the 3 × 30 s set after rests of 1 min, 3 min, and 5 min to estimate recovery time to first-interval performance.
  * Dominant vs nondominant hand: run both hands; compare interval shapes and totals.
  * Peg tension: compare light vs heavy-spring pegs (measured with a simple force gauge or labeled by the manufacturer).
  * Fitness or musician subgroup: compare class averages for students who self-identify as athletes or instrumentalists with others.
  * Class statistics: compute means and ranges for each interval; add error bars to graphs.



====Safety Precautions====
  * Avoid pinching skin; use intact, smooth pegs only and replace damaged ones.
  * Stop immediately if pain, cramping, or numbness occurs; shake out the hand and rest.
  * Limit total sets to prevent overuse; alternate hands if doing multiple trials.
  * Clean shared pegs or hands between users to reduce germ transmission.




====Questions to Consider====
  * Why do counts usually decrease across intervals? (Oxygen delivery cannot keep pace with demand; anaerobic pathways contribute more, yielding less ATP per glucose.)
  * What causes the burning sensation? (Accumulation of lactic acid and related metabolites interfering with contraction.)
  * Which fiber types are recruited as the task continues? (Slow-twitch dominate early under aerobic conditions; fast-twitch are recruited as intensity and fatigue increase.)
  * How does rest restore performance? (Oxygen replenishes, lactate is cleared, and phosphocreatine stores are rebuilt.)
  * What controls make this a fair test? (Same peg type, timing, instructions, and rest; only the intended variable changes.)