阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。
Do you feel the cold? ____ the answer is “yes”, then why not try a cold bath or shower? This unusual advice comes from a natural health therapist(治疗专家) in Germany, ____ research is about the effects of cold water.
Most people are brought up to believe that it’s important for them ____ (keep) warm during the cold weather, with extra clothing and heaters, but research shows that the opposite ____ (be) true. At a German health centre, hundreds of ____ (visit) follow this advice by taking ____ (they)first cold bath at 6 am, and come out feeling much more ____ (relax). This is due to the fact that the cold water ____ (increase) blood sugar levels, the heart beat and breathing rate. Research at the medical centre of Hanover has shown that those taking daily cold baths have 50% ____ (few)colds and breathing problems than those who don’t. Studies in London have also proven that such treatment will help protect against heart attacks. For those people who find the idea of such behaviour unthinkable, then doing exercise such as running or cycling regularly is a good alternative. So, next time you’re suffering ____ the cold, don't sit and comp lain, take action!
的是（ ）