T = array2table(rand(30,8), ...
'VariableNames', {'var1' 'var2' 'var3' 'var4' 'var5' ...
'var6' 'var7' 'var8'});
However if you want to assign other properties besides names, you have to do that separately, unlike the table command,
T.Properties.VariableUnits = {'kg' 'm' 'W' 's' 'g' 'kg' 'm' 'W'};