Exercise in Summer
Dogs don’t just die in hot cars. Recent research shows that exercising dogs in the summer heat can also put them at risk of heat stroke, particularly if they are older or brachycephalic (flat-faced). To keep them safe, SPCA recommends exercising your dog early in the morning or in the evening when temperatures are cooler.
Exercise your pets early in the mornings or in the evenings to avoid the heat of the day. Avoid long and strenuous walks on hot, sunny days, and steer clear of prolonged sun exposure. Take your pets to an area that has shade or a place for them to swim so they can take a break to cool off, and if they want to slow down or stop, follow their lead. Also, avoid walking animals on hot tarmac or sand as this can burn their feet, see 'The five second rule'
Source - SPCA