Biking

Central European Adventure Tours, Jáchymova 4, Praha 1 (tel./fax 222-328-879; also online), rents touring bikes and arranges whatever transport you need for them. The best biking is outside Prague, on the tertiary roads and paved paths in the provinces. They will suggest routes and provide maps. A 1-day guided biking trip around Karlstejn Castle and Konepruské Caves costs 680Kc ($32/£16). Call ahead to make arrangements. Tickets and information are also available at the PIS office, Rytírská 31, Praha 1.

Golf

Czechs are rediscovering golf on the new tournament-caliber course with a world-class view at the Praha Karlstejn Golf Club, 30 minutes south of Prague. You can improve your game during cold weather at the Erpet Golf Center, Strakonická 510, Praha 5 (tel. 257-321-177). Opened in 1994, the renovated innards of a Communist-era sports hall now has a tropical setting of driving platforms, with pitching and putting greens on Astroturf and interactive video simulators. It's open daily from 7am to midnight. Take metro line B to Smíchovské nádrazí. The price is 300Kc ($14/£7) per hour, including the use of a well-equipped fitness center.

Health & Fitness Clubs

On the 25th floor of the Corinthia Towers Hotel, Kongresová 1, Praha 4, the Level 25 Health & Fitness Centre (tel. 261-191-326) provides weight machines, free weights, exercise bikes, step machines, a small pool (surrounded by glass with an expansive view of the city), a sauna, and a solarium. The modern facility also offers tanning beds, squash courts, a whirlpool, and massages. A 1-day pass is 560Kc ($27/£13). Daily 10am to 4pm. Squash courts can be rented for 500Kc ($24/£12) per hour. The club is open Monday to Friday from 6:30am to 10pm and Saturday and Sunday from 7am to 10pm. Take metro line C to Vysehrad.

World Class gym at Václavské nám. 22 (tel. 234-699-100) is a new large health club in the city center, where you can try classes including aerobics, spinning, yoga, or Pilates, or work out in the gym for 500Kc ($24/£12) a day. It is open Monday to Friday 6am to 11pm, Saturday 7am to 10pm, Sunday 9am to 10pm.

The Erpet Golf Center (Fitness Center), Strakonická 510, Praha 5 (tel. 257-321-177), has modern fitness machines, free weights, electronic rowers, and treadmills. There's also a relaxation center, with a dry sauna and a coed whirlpool that's usually open to the public. Use of the fitness and relaxation centers costs 300Kc ($14/£7) for 3 hours. It's open Thursday through Tuesday from 9am to 11pm, Wednesday from 9am to 9pm. Take metro line B to Smíchovské nádrazí.

Jogging

Prague's sometimes thick smog makes jogging more like smoking, but on clear days -- and there are many in summer -- the air is bearable. For the most scenic run, jog on the paths atop the Vysehrad citadel, accessible by tram no. 3 or 16 from Karlovo námestí. The parks at Kampa and Letná are also good places to run. The paths crisscrossing Petrín Hill offer a challenging uphill route. The best no-traffic, long-distance runs -- flat, long, and mostly tree-lined -- are found at Stromovka or Divoká Sárka parks.

If you want to run through central Prague, use the traffic-restricted walking zones as often as you can. For an approximately 2.5km (1.5-mile) circuit, start at Mustek at the end of Wenceslas Square, run down Na Príkope through the Powder Tower (Prasná brána) to Celetná Street all the way to Old Town Square, run around the Hus monument, run back to Zelezná Street past the Estates' Theater on to Rytírská Street, and run back to Mustek. This route is virtually free of cars, and your feet will be pounding the bricks. Try running in early morning or late evening when the streets aren't packed with crowds.

The Prague International Marathon -- The Prague International Marathon (PIM), Prague's premier annual civic-pride event, has grown by leaps and bounds since it was first run in 1995. The 42.2km (26.2-mile) race attracted just under 1,000 runners in its first year, but in 2004 it had more than 8,000 runners from 60 countries. That number combined with the Fun Run, a 6km (4-mile) race for families, totals about 40,000 people or even more.

Many come to take advantage of the unique chance to run through Prague's cobblestone streets without having to dodge Skodas and trams. Others, especially nonrunners, love the festive atmosphere in Old Town Square, the music groups that line the race routes, and, of course, the great Czech beer that flows across the finish line.

My husband John, a consummate couch potato, was so inspired by the event that he was motivated to train just enough to run the 1999 marathon (although he missed his goal of breaking 4 hr. and has yet to attempt it again).

The marathon route takes runners through the very heart of old Prague. The final stage of the race winds through the quirky streets of Old Town and eventually ends back at Old Town Square. Public transport on race day is free for participants who show their start number. A free massage and plenty of affordable pivo (beer) is available in the finish area, along with many other energy-restoring liquids.

For those who would like to give it a shot, the race takes place usually on the third Sunday in May, starting at 9am in Old Town Square (Staromestské nám.). Marathoners can register for the race in person at the PIM EXPO, at Záhoranského 3, Praha 2. You can also register in advance by phone or online (tel. 224-919-209). The registration fee for the full marathon is 1,750Kc ($83/£42); for family fun runs, the cost is about 300Kc ($14/£7). All marathon runners must get their timing chip (shorter distances are not officially timed).

Swimming

Summer doesn't last long in Prague, and when it arrives, many city dwellers are only too happy to cool off in one of the city's many pools. In addition to the hotel pools, there's the Dzbán Reservoir, in the Divoká Sárka nature reserve, Praha 6. Dzbán is fronted by a grassy "beach" that can -- and often does -- accommodate hundreds of bathers. There's a special section for nude swimming and sunbathing. To reach Sárka, take tram no. 26 from the Dejvická metro station. If you prefer a swimming pool or the weather doesn't cooperate, visit one of Prague's best aqua centers. The Letnany Lagoon, Tupolevova 665, Praha 9-Letnany (tel. 283-921-799) has got a full-length pool as well as Jacuzzi and toboggan, which is a good fun for the whole family. You can also get a little refreshment and a drink while around the pool. The Lagoon is open Monday, Wednesday, and Friday 6 to 9am and noon to 10pm; Tuesday 7 to 9am and 4 to 10pm; Thursday 7 to 9am and noon to 10pm; Saturday and Sunday 9am to 10pm. Admission is 140Kc ($6.65/£3.35) adults, 70Kc ($3.35/£1.65) children for 2 hours. To get there take bus no. 210 from metro line C Holesovice to the Tupolevova stop at Letnany.

Tennis

At the First Czech Lawn Tennis Club Praha at Stvanice Island (tel. 222-316-317), you can play on the courts where Martina Navrátilová and Ivan Lendl trained. The rental rate is from 370Kc to 630Kc ($18-$30/£8.80-£15) per hour per covered court.

Yoga

Yoga's popularity has been growing rapidly in Prague, and yoga classes are now on the menu for most fitness centers. One standout is Lotus Center, on Dlouhá 2, Praha 1 (tel. 224-814-734), which offers classes in English for 65Kc to 100Kc ($3.10-$4.75/£1.55-£2.40)