* FTSE 100 down 0.5 percent * Index range-bound, capped around 6,800 -analysts * Sports Direct gains on strong Christmas profits * Ex-divs knock 14 points off index By Tricia Wright LONDON, Feb 19 (Reuters) - Britain's top shares lost ground on Wednesday as analysts bet the strong rally that followed a slump in emerging markets has run out of steam, though Sports Direct gained on robust profits. At 1148 GMT, the FTSE 100 was down 35.50 points, or 0.5 percent, at 6,760.93 points. It hit 6,810.48, its highest since late January, earlier in the day. The weakness followed a rally of around 6 percent since early February. Analysts reckoned on the index levelling off, around 1.5 percent shy of a peak hit in late January, before political and economic concerns in emerging markets took their toll on equities. It has been trapped in a range between around 6,400 to 6,800 since late October. "I don't think the traction is there to really push us back to the highs that we saw earlier this year," CMC Markets senior market analyst Michael Hewson said. "It's going to be very difficult to break us out of that range." Britain's biggest sporting goods retailer Sports Direct bucked the weaker trend, up 6.5 percent in brisk trade after unveiling a 14.6 percent rise in profit in its Christmas quarter and saying it was confident of hitting its full-year target. "We maintain our view that Sports Direct is well positioned to drive long-term growth both in the UK and overseas," analysts at Liberum wrote in a note, keeping their "buy" rating on the stock. Trading volume in Sports Direct stood at 1-1/4 times its 90-day daily average, against the UK benchmark on just a third. Firms trading without the attraction of their latest dividend knocked a hefty 14 points off the index - namely AstraZeneca, Barclays, Carnival, GlaxoSmithKline and Reckitt Benckiser.