While some people simply throw a few items they'll need into their gym bags before heading to work out, it's easy to leave out things that you need if you don't plan ahead. The exact contents of your gym bag will differ based on the activities you do at the gym and your personal preference, but there are a number of items you should consider packing before your next trip to the gym.

Clothes and Footwear

When packing your gym bag, add a change of clothes and matching accessories so you don't have to wear your sweaty gym clothes home. Bring extra socks to ensure that your feet don't get too sweaty while you work out, and toss in an extra pair of shoes if you have room in your bag as well. Add flip flops or shower shoes if you plan on showering at the gym, and include a laundry bag or several plastic bags to put damp or sweaty clothes and footwear in after you take them off.

Workout Equipment

Some workout and sports equipment is easy to remember; if you're going to play racquetball, for example, you'll bring your racket. Double-check to make sure that you have any other equipment you might need, however. Don't forget your odometer, lifting gloves, eye protection or other smaller pieces of equipment. If your gym requires you to supply your own lock for locker space, make sure that you bring it as well.

ID Holder

An ID holder isn't necessarily an essential piece of equipment, but it definitely comes in handy when going to the gym. Most ID holders have enough space to hold your driver's license and gym membership card, plus a few dollars so you can pick up any incidentals at the store or a drink at the juice bar.

Water and Snacks

Proper hydration is essential when you're working out. Instead of paying several dollars for bottled water at the gym, bring along your own in a water bottle. Adding in a few healthy snacks can help keep you energized while you work out and can also provide your body with much-needed protein and carbohydrates once your workout is finished.

Hygiene Supplies

Personal hygiene is important, especially when you've been sweating at the gym. If your gym has a shower, travel-sized shampoo, body wash and facial wash packets let you get clean without taking up a lot of room and can be refilled later at home if necessary. Don't forget the towels either, as it's cheaper to bring your own than rent them. Other hygiene products such as deodorant and hair care products should be included in your bag as well, as should feminine products if you need them.

First Aid

Though gyms should have first aid materials on site, bringing along your own bandages, antibacterial wipes and other basic first aid equipment means that you can treat small scrapes and cuts quickly. Optional first aid equipment such as knee or ankle braces can be added to your gym bag too as preventative measures if you perform exercises that place a lot of stress on specific joints.

Media Player

A lot of people listen to music while they work out. If you carry an mp3 player or other media player with you to the gym, make sure that it's fully charged and loaded with your workout playlist before you put it in your bag. Bring along accessories for it as well, including a case that you can secure to your arm or clothing and a spare set of headphones in case your primary headphones stop working or become damaged.

Post-Workout Supplies

To save time after your workout, bring along anything that you need to skip heading home if you have plans later in the evening. This includes textbooks or work materials if you have classes or work in the evening, any items that you'll need to meet up with friends afterward and some make-up and perfume or cologne if you plan on going out to dinner with a special someone.

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