Temptation Bundling
Pair a pleasurable indulgence with a task you find hard to do.
Think about something that moves you, makes you happy (eg. Playing badminton/playing guitar/running/gymming/taking strolls..etc.)
Plan to do this activity only in the time that makes you dull for studies. This shall motivate you to remain active during the dull/difficult time even in winters.
I know it works because I have tried it. I have paired learning music software (my passion) with waking up early(difficult job). I get up excited in the mornings because of this motivation.
Hope it helps.
