From Lakeland Leisure Park there's a flat start eastwards on the NC 700 with a serious 60 metres of ascent from the B5277 to Allithwaite, following Church road more or less straight through Allithwaite. The Pheasant Inn is a possible drinks stop. There is a pleasant small church (St. Mary's), on the LHS at the north end of the village. From Allithwaite it's a descent on the NCR70 (join at the junction of Church road and Green Lane) to Cartmel, and Cartmel back to Flookburgh is also virtually all downhill on the NCR700.
Length is 8.5 miles.
A more direct 7-mile loop with less ascent is possible by using Green lane (just east of the NCR700). A longer 15.5 mile loop to near Haverthwaite (similar to the Collin's Cumbria Route 13) is possible. This climbs steadily up the NCR700 from Cartmel up Beck side, ascending a total of 95 metres but pretty well graded, to just before High Brow edge. There is then a steep 160 metre drop down to Low Wood, picking up either the NCR700/70 westwards (or the cycle path) to Greenodd (adding around 2.5 flat miles along the river Leven each way). The route returns via the flattish B5278 to Flookburgh, with a slight easy up-and-over at Holker.