What would you do if one of your adult learners refuses to do a kinaesthetic activity on the pretext of not being a kinaesthetic kind of learner?

First I would explain to the student that it is part of the curriculum to do kinaesthetic activities. We can not force a person to do something they do not want to do; so I would find another activity for the student that did not involve kinaesthetic activity.

The answer is there within your question.

Actually learning needs a conducive environment. In the absence of a conducive environment you can't expect the desired results from kids as well as from adults.

If an adult does not feel comfortable in Kin aesthetic kind of learning then he can't learn by this method. We should not force him for it. Better is to take an alternative method to achieve the goal - learning. 

Will enumerate to him the benefits of the activity. And join him do the activity to lessen his/her feeling of awkwardness. And finally acknowledge his efforts.

As someone who as a student was often 'forced' to participate in activities for the sake of participation, I eventually disliked these sort of activities. I do not believe that every person learns or benefits from the same method as another student. If a student does not wish to participate, let them sit it out. It's one thing for a person to venture outside their comfort zone, it's something else to force them to do it. Insisting that someone participate in an activity they're not comfortable with may end up being counter-productive. 

Let them sit it out if they're not comfortable participating. 

If the student is not interested in the kinaesthetic process, then we should encourage the learner to demonstrate his suggestions or such activities that exhibits his originality, is interesting for his peers,and could be easily implemented during of the lessons.

try to make him or her  aware of the importance of your course activities in our daily life  and try to help     him first then repeat the activity an other time and carefully keep him do it by himself then encourage him by using words like 'good''go ahead' '

• I'll try to persuade him by focusing on the importance of this course in our daily life .
• I'll help him to do it gradually:First  by helping him then let him do it by himself
• If this method fails to achieve the goal,I'll turn to plan B by using another method to teach him

I fully agree with the answers been added by EXPERTS............Thanks.

learning needs a environment form same field