On Cloudmonster 2: crushed cushions and loss of propulsion

WARNING: ReeFix provides this diagnosis EXCLUSIVELY for educational and informational purposes. Any structural modification or the use of worn footwear can severely alter running biomechanics, increasing the risk of musculoskeletal injuries. The application of chemical adhesives or non-approved inserts can compromise the torsional stability of the footwear, making it unsuitable for high-intensity sports activity.

CAUSE A: Polymer yield and structural fatigue (Probability: 63%)

Key signs/indicators:

• Presence of deep, permanent wrinkles on the outer surface of the Cloud elements, even at rest.
• Sensation of a "wall" or hard impact during the landing phase, with a clear loss of cushioning.
• The cushions do not return to their original geometric shape after load removal.
• Sensation of a "flat" run lacking reactivity, especially during the toe-off phase.

Why it happens: The Helion Superfoam, a block copolymer, undergoes irreversible plastic deformation due to repeated cyclic loads. The internal micro-air cells collapse, and the polymer walls yield, losing the ability to recover their shape. This nullifies the lever effect of the Speedboard, drastically reducing propulsion.

Quick checks:

1. Place the shoe on a flat surface: observe if the sole rests uniformly or if it shows abnormal lateral inclinations due to asymmetric collapse.
2. Manually compress a crushed cushion: if it does not recover its previous elastic shape, the yielding is advanced.
3. Compare the stack height (midsole thickness) with a new shoe or model references. A loss of 2-3 mm is already significant.

Costs and operational decision: Chemical or physical regeneration of an exhausted foam is not feasible with artisanal interventions. The cost of a professional intervention to "repair" the foam is uneconomical, as it would require the replacement of structural components not designed to be modular.

• DIY repair: Not possible to restore original functionality. You can try to partially compensate with High-performance cushioning insoles for On Cloudmonster 2 (cost: 20-50€), but this is a palliative for non-competitive use.
• Consult a technician: A sports podiatrist could evaluate the impact on your biomechanics and suggest custom orthotic insoles (cost: 150-400€) to redistribute loads and extend use for low-impact activities.
• Replace the device: To maintain sports performance and prevent injuries, this is the most reliable choice.

Experience insights: "This often happens when runners exceed their ideal weight or have a particularly aggressive running dynamic (e.g., marked heel striking), concentrating stress on a few Cloud elements, accelerating local collapse."

CAUSE B: Excessive mileage and natural wear (Probability: 27%)

Key signs/indicators:

• The shoe has an estimated mileage exceeding 500-600 km.
• Visible and widespread wear of the rubber tread, with loss of the original pattern in points of greatest friction (outer heel, forefoot).
• Gradual and generalized loss of cushioning and reactivity over time.

Why it happens: Every polymeric cushioning material has a limited life cycle of compressions and extensions. Beyond a certain threshold of use, the molecular structure of the foam naturally degrades, losing its elastic properties even without immediate visible collapse. This is the normal end-of-life for the product.

Quick checks:

1. Check activity history on tracking apps (Strava, Garmin Connect) if associated with the footwear.
2. Examine the tread: if the rubber is very worn, it is a clear indicator of high mileage.

Costs and operational decision: This cause indicates the end of the shoe's useful life for its original performance.

• DIY repair / Consult a technician: There are no economical interventions that can restore the mechanical properties of an end-of-life foam.
• Replace the device: This is the most logical and recommended solution to ensure safety and performance.

Prevention tips: Monitor the mileage of your footwear and replace them preventively between 500 and 700 km, depending on your weight and running style.

CAUSE C: Thermal degradation or improper storage (Probability: 10%)

Key signs/indicators:

• Premature stiffening of the foam even at low mileage.
• Abnormal and asymmetrical deformations of the cushions, sometimes with superficial micro-cracks.
• The foam feels "dry" or less flexible to the touch.

Why it happens: Prolonged exposure to high temperatures (e.g., leaving shoes in the car trunk in summer, drying them near direct heat sources) accelerates the glass transition of the midsole polymers. This makes the foam stiffer and more brittle, much more susceptible to permanent collapse even under modest loads.

Quick checks:

1. Analyze storage habits: has the shoe been exposed to direct heat sources or intense sunlight for long periods?
2. Visually inspect the cushions: look for micro-cracks or an "aged" and stiff appearance of the foam that is not proportional to general wear.

Costs and operational decision: Thermal damage is irreversible and irreparably compromises the polymer structure.

• DIY repair / Consult a technician: There are no effective repair options for thermal degradation of the foam.
• Replace the device: The shoe has lost its original characteristics and is at risk of further failure.

Typical user error: Drying wet shoes on a radiator or in a dryer to speed up the process, destroying the elastic properties of the midsole.

WHICH ONE IS YOURS?

To decide quickly:

1. Visual and tactile inspection: If the cushions are visibly crushed, do not recover their shape, and you feel a "wall" sensation (CAUSE A), the foam is compromised.
2. Mileage check: If the shoe has exceeded 500-600 km (CAUSE B), it has reached its end of life.
3. Environmental conditions: If it has been exposed to excessive heat or improper storage (CAUSE C), degradation is likely.

Operational decision: If the shoe shows clear signs of yielding (CAUSE A) or has exceeded the recommended mileage (CAUSE B), replace the device. If the wear is asymmetrical or you suspect a biomechanical problem, consult a technician (podiatrist/orthopedist) for a thorough evaluation and possible prescription of orthotic insoles; you can also consider using High-performance cushioning insoles for On Cloudmonster 2 for non-competitive use, but they will not restore the original propulsion.