3. High Knees
High knees are a great field drill and also a workout you can perform anywhere. Aim to get your thigh at least parallel to the ground when you raise your knee. Keep your foot flexed on the raised foot.
Start with your feet hip-width distance apart. One at a time, lift each knee up high toward your chest. Quickly and explosively switch knees. Repeat for the prescribed time.
4. Mountain Climbers
Mountain climbers blast your core and hip flexor muscles while burning calories and giving you a great workout.
Start in a plank position. Bring one knee up toward your chest, keeping your foot off the ground as you bring it forward. Quickly alternate your legs back and forth. Maintain a braced core, and do not allow your hips to sag during the set. Repeat for the prescribed time.