The phrase "exercise difficult" is not grammatically correct or usable in written English.
"Exercise" is a noun or verb and cannot be used as an adjective in this context. Instead, you could say "difficult exercise" or "challenging exercise." Example: "The trainer designed a difficult exercise program for his clients to improve their strength."
But it will be difficult to say goodbye to this three-month interlude of enlightening exercise, difficult to trade in the outdoors, the physical expenditure, the unpredictability of every day, the adrenaline pump that has been propelling me through cycling's inherent hazards, for the daily repetition of home and office, home and office.
However, the heterogeneous nature of the exercise intervention trials makes determining the appropriate program variables (frequency, intensity, duration and type of exercise) difficult.
I found exercise difficult, and like many girls my age, I ate to comfort myself.
They find exercise difficult and fatigue quickly, presumably since they initially rely on blood glucose from exogenous sources for fuel.
When people are unable to exercise on land, or find land based exercise difficult, aquatic programs provide an enabling alternative strategy.
Similar to previous findings [ 27], some interviewees cited long working hours and related fatigue as reasons for finding exercise difficult to fit in.
They considered the exercises helpful but some found a few of the exercises difficult to understand.
"Exercise dissipates difficult emotions," says Hodson.
In Iran, by contrast, life is a daily exercise in difficult compromises that temper Islam with modern society's demands.
"Then it became an exercise in difficult watchmaking, to be as thin as possible with maximum water resistance," he said.
For busy executives, balancing work with family, a hobby or even regular exercise is difficult at best.
