There will be a certain degree of temporary increase. During a spa hot tub session, due to: • Increased heart rate • Enhanced thermoregulation • Accelerated blood circulation The body's energy expenditure will be slightly higher than in a completely resting state. This means that the metabolic level does increase during the bath.

In most cases, the increased heart rate caused by soaking in a spa hot tub is a physiological increase in heart rate, not a pathological problem. This is a normal regulatory response of the heart to maintain stable blood circulation and ensure blood supply to vital organs.

Spa hot tubs: • Improve metabolism through warm water, water pressure, and circulation • Provide a more stable and longer-lasting metabolic boost • Focus more on the overall system's synergistic regulation Steam saunas: • Stimulate metabolism through high temperature and humidity • Produce a stronger but shorter-lasting metabolic response • Rely more on the body's tolerance

Showering before entering a spa hot tub is not merely a formality of hygiene, but a fundamental usage standard proven over a long period. Spa hot tubs are high-temperature, closed, circulating water systems; any contaminants entering the water will be repeatedly amplified through circulation.

Some people feel tired after soaking in a spa hot tub, even mistakenly believing they've "burned a lot of energy." This "fatigue" is more of a reaction to relaxation than a result of high-intensity energy expenditure.

In most cases, cloudy water in a spa hot tub is the result of a combination of factors: • Insufficient disinfectant • Decreased filtration efficiency • Accumulation of human contaminants • pH or hardness imbalance • Insufficient circulation time • Excessive water usage cycle