Final answer:
The workers are physically affected by the cold wind in their surroundings.
Step-by-step explanation:
The detail that best supports the idea of workers being physically affected by their surroundings is the line 'And the cold wind you breathed / Was moving under your skin.' This suggests that the cold wind penetrates the workers' bodies and has a direct physical impact on them. It implies that the workers are exposed to harsh weather conditions, which can have adverse effects on their health.
Learn more about Effects of surroundings on workers' physical health